Learn English – Lack of it / Lack thereof

In the Southern part of the United States, "sweetie" and "honey" are sometimes used by women or gay men when speaking to others in various situations in public. For instance, a woman at a clothing store might ask a man or a woman, "Do you need any help, sweetie?"

It is not used by straight men except in a flirtatious/sexual or condescending way. The above would not have worked if it were a straight man, as it is supposed to be a 'professional' and not flirtatious atmosphere.

In your above comments, you are coming off as both overly sexual and condescending. "Let me get that for you, sweetie" seems to imply she is incompetent when a man says it to a woman (who are not together romantically), whereas "Let me get that for you" has none of that connotation.

'Sweetie' and other pet names are generally NOT used until you are in an established relationship with someone. Boyfriends and girlfriends may do so, but before that, while dating, it's a little presumptuous and definitely implies that you are together.

You could rephrase the sentence to include the consumer.

The fitness industry makes a lot of money from poorly informed and misinformed consumers.

As stated, your second option suggests that the correct information doesn't exist yet in the universe, which could well be true or what you mean, but it feels like you should pin it on the consumers instead of the state of knowledge about exercise and health. Alternately, if you point is that we just don't know much about exercise, I think you have a great option already.