Slang dictionary coverage of 'from hunger'
Harold Wentworth & Stuart Flexner, Dictionary of American Slang, first edition (1960) provides the following entry for "from hunger":
from hunger Inferior; cheap; ugly; lowbrow; disliked; unwanted; corny; hammy. 1935: Playing [music] from hunger: similar to 'corny,' meaning playing in a style to please the uneducated masses." Peabody Bulletin, Dec. 42/2. 1951: "I started giving the three witches at the next table the eye again. That is, the blonde one. The other two were strictly from hunger." J.D. Salinger, Catcher in the Rye, 56. Orig. assoc. with jive, swing, and jazz use c1935.
The Peabody Bulletin, cited as the source of the 1935 quotation, is a publication of the Peabody Conservatory of Music, in Baltimore, Maryland. The notion that "from hunger" originally applied to playing in a popular style in order to avoid going hungry has a special edge coming from the Peabody Conservatory, a bastion of highbrow music.
J.E. Lighter, Random House Historical Dictionary of American Slang (1993) divides divides its entry for "from hunger" into adverbial and adjectival parts, and finds one match for the adverbial sense of the word that antedates the one in the Peabody Bulletin:
hunger n. In phrase: from hunger, 1. adv. emptily, foolishly, or ineptly; (occ.) to a dismaying degree. [First two citations:] 1934 Jevne & Purcell Joe Palooka (film): I'm not talkin' from hunger! 1935 in D[ictionary of] A[merican] S[lang]: [the Peabody Bulletin quotation reproduced above.] 2. adj. most unsatisfactory, unappealing, untalented, unattractive, etc.; no good. [First two citations:] 1939 "E. Queen" Dragon's Teeth 29: That theatrical lead is strictly from hunger, I tell you! 1939–40 O'Hara Pal Joey 10: Two months ago, Joey was strictly from hunger, as they say.
The "from hunger" line presumably came from Jack Jevne, who wrote the screenplay for Palooka (based on a long-running newspaper comic strip by Ham Fisher). According to Wikipedia, Jevne was born in Provo, Utah, in 1892; his father was "a professional billiards player," and his mother "a Swedish immigrant."
On the other hand, Leo Rosten, The Joys of Yinglish (1990) [combined snippets], asserts that "from hunger" is Yinglish (his term for an amalgam of English and Yiddish):
from hunger Authentic Yinglish. From the Yiddish fun hoonger. This locution has long been popular in theatrical literary and critical circles. "Strictly" is often added to emphasize one's conviction. 1. Anything done out of severe necessity, rather than choice. "He wrote it without pleasure—but from hunger." 2. Second or third rate.
I'm somewhat suspicious of this claim, however. In Hooray for Yiddish! A Book About English (1982), Rosten notes two ways in which Yiddish-inflected English uses from distinctively: (1) in place of of ("From German: von, via Yiddish: fun"); and (2) (habitually at the beginning of a sentence where, in normal English, it would more likely appear at the end (as in "from that he makes a living?" and "from that you could faint"). He freely cannibalizes all of these discussions in his later book—but the "from hunger" discussion he adds to it, because it isn't in the earlier book. So from this treatment I should feel confident that Rosten knows from the origin of "from hunger"?
Lillian Feinsilver makes a similar claim in The Taste of Yiddish (1980) [combined snippets]:
The slang "from hunger" is probably from Yiddish ER SHABT FUN HUNGER (He's starving from hunger; hence, is in need, inadequate), where the "from" again takes the place of "of." Other phrases from the entertainment world, like "strictly from borsht," referring to the style associated with the borsht circuit, may be related.
Well... maybe. But where are the pre-1937 examples of "from hunger" (or "fun hunger" or "fun hoonger") being used in specifically Yiddish or Jewish settings in the critical, sarcastic, or dismissive way that "from hunger" is starting in 1934/1935?
'From hunger' in Google Books and Elephind newspaper search results
A Google Books search for "from hunger' and various specific forms of that phrase yields no matches from the 1920s or from the first half of the 1930s in the relevant sense. In fact, the earliest match it finds is to S. J. Perelman's book, Strictly From Hunger (1937). Other matches appear beginning in 1939. From John O'Hara, Pal Joey, excerpted in The New Yorker, volume 15, part 3 (1939) [combined snippets]:
I told you the details and how I got creamed out of the hotel spot in Ohio & came here and made this connection. For a while I was from hunger but suddenly clicked as it were over night. With me it was one of those things, just one of those crazy things. One nite singing a lung out for dopes that wouldn't know it if I was Toscanini, Al Rinker, or Brooks John or myself. All they cared about was if I sang "Deep Purple" 75 times a nite and they were satisfied.
From "American Slang: A Glossary for Elder Readers," in Punch (1939) [combined snippets]:
Strictly from hunger. Pretty bad; in fact terrible. The "strictly" is optional. For example, you might say "As a poet, Shakespeare's from hunger." Of course you'd be wrong, since Shakespeare happens to be a pip of a poet, but then you've been wrong before, haven't you? (William Shakespeare—remember? He was one of the collaborators on Palgrave's Golden Treasury.)
And from the entry for "Artie Shaw," in Current Biography Yearbook, volume 2 (1941) [combined snippets]:
An agency signed him for a larger band using the same basic instrumentation, with other instruments added. They opened cold in a New York hotel, and though other New York jobs followed, none served to establish the group. On the road they found themselves — as musicians say — working "strictly from hunger." The agency dropped them, and they were on their own once more.
An Elephind search of multiple newspaper databases returns a match from Helen Menken, "Man About Manhattan," in the the Orange [Texas] Leader (November 7, 1937):
George, I've been wondering how in the world you ever became a columnist And why. Won't you write a story about it one day? I became an actress "strictly from hunger." We were pretty poor. So I went to work when I was four. Believe it or not, I was a Shakespearian actress at four. I was "Mustard Seed" in "A Midsummer Night's Dream"!
Another interesting early occurrence appears in Tommy Dorsey & George Lottman, "Love in Swingtime," in the [Honolulu, Hawaii] Nippu Jiji (April 29, 1939), which includes this glossary entry:
Strictly from hunger: out of a job.
and this in-situ occurrence of the phrase:
“What’s the dirt?” I asked him.
“NBC expelled three pluggers for hanging around a woodshed,” said Gene. “Decca is looking for a good groanbox artist to do a recording date with the Boswell Sisters,”
“I don’t know of a good loose squeezeboxer,” I said. “Here, Gene, meet Biff Brown, a new clarinetist I discovered when I played a one-nighter in Maine last year.”
“Strictly from hunger?” Gene whispered to me.
“Gene, how do you always know when a guy is looking for a job?”
Conclusions
The origins of "from hunger" are obscure, but it seems to have achieved its first flash of popularity in music circles where "playing from hunger" meant "playing to the lowest common denominator of popular taste." Another very early sense of the term was (as the Tommy Dorsey article suggests) "out of a job." From there, it seems to have rapidly acquired the broader meaning of "low-quality or low-talent [entertainment]," and from there the still broader meaning "inferior"—as in the example of the brand of pickles mentioned in the OP's quotation.
The persistent suggestion that "from hunger" is of Yiddish origin is difficult to definitively verify. S.J. Perelman's 1937 book, Strictly From Hunger invites readers to find that connection, since Perelman was Jewish). However, the phrase was already recorded in 1934 and 1935 in a movie script by a guy from Utah and in the house periodical of the Peabody Conservatory of Music. With some other terms that are unmistakably of popular Yiddish origin, Yiddish versions of the word or phrase are recorded in Yiddish or English Jewish sources. But with "fun hoonger" and "fun hunger" and "from hunger" Google Books searches yield no pre-1937 matches with an unmistakable Jewish connection that reflect the sardonic sense of badness that the earliest non-Yiddish instances of the phrase do.
Fred Kogos, Book of Yiddish Proverbs and Slang (1970) offers this proverb of unknown date (but presumably older than the 1930s):
Fun hunger shtarbt men nor in a hunger-yor. [You can die of hunger only in a year of famine.]
But there is nothing metaphorical or sardonic about this usage—and no clear-cut examples of crossover use in the U.S. entertainment industry prior to 1937. I remain persuadable on this point, but not yet persuaded.
‘Juices’ is a kind of slangy term that means ‘a person’s vitality or creative faculties’. The creative faculties are of course what is referenced in the expression mentioned in the question linked to by jwpat7 in the comment above; in this case, it’s the other meaning we’re looking for.
Since a person’s vitality is seen here as a kind of ‘juice’ (originally most likely referring on some level to bodily fluids: especially blood was, in Mediaeval times, often considered to be a source of energy, health, and vitality in humans), it makes sense that it should be set ‘flowing’, since that’s what liquids do.
This meaning is extended from the meaning the OED has as sense 2:
The fluid part or moisture of an animal body or substance; now usually in pl. the various liquid constituents of the body, the bodily ‘humours’
Obviously, if you think of it as being ultimately just a kind of euphemism for blood (and sweat and bile and all the other humours), getting it to flow, and flow faster especially, would be a sign of physical exertion or excitement: when we run, our blood actually flows faster, and our pulse increases.
The phrase is often also used in a sexual manner, where the reference is to the various kinds of sex-related bodily fluids that are released when people become aroused. Whether the sexual meaning came first or the exertion meaning came first (or whether they are really to be separated at all), I do not know; I cannot find any quotes for that. But it is clear that they are both in use.
In the quote from your NYT article, the meaning is definitely that of physical exertion–based excitement. He is comparing the ‘rush’ he gets from driving to a kind of race where he’s not going to let anyone pass him and be faster than him.
Best Answer
In the context of the lyrics I interpret it as meaning that she shouldn't be too naive and think that just being nice (smiling to people) will mean people won't try and use her. She has to be aware that other people are not always good and should look after herself because "there's a lot of bad" out there.
Of course song lyrics can often be interpreted in different ways so other people may disagree with me on this.