I am pretty sure that the rules never clarify beyond what you have already quoted, and I am certain that the rules you have quoted are not definitive on this point.
I, and literally everyone I have ever played with or talked to, have always assumed that casting spells with both material and somatic components takes one hand. Never really paid very much attention to it. But I suppose the assumption was either that the material component is consumed before the gesturing takes place, or else that the gesturing is done with the hand holding the material component.
This is a hack in the crafting rules, not in the fabricate spell.
That said, in the absence of a hard rule I could not find, there are two contradictory implications at various points in the rules:
1) It is at least strongly implied that 3.5e coins are pure metal. The PHB, on p. 112, notes that a gold piece weighs about 1/50 lbs, and also that 1 lb of gold actually costs 50 gp. There is no reason to think that the "1 lb of gold" is intended as an alloy, so the implication is that coins are actually pure gold, as silly as that is. (Gold is soft and not very durable in pure form. At the absolute minimum, the implication is that if one buys "a pound of gold" one gets exactly coin-grade gold alloy, which does not change the argument here.)
The same logic holds for platinum, silver, and copper, which is a little insane, but it's a simplifying assumption for a game and it's what the rules say.
2) Crafting, on the other hand, makes a simplifying assumption in the other direction: That materials account for 1/3 the total value of any object. I.e., a bow costs more than a stick and a string, because it took someone time and skill to put it together, leather saddlebags are worth more than a bloody cow hide because tanning is a filthy disgusting process, etc.
This is just as silly an approximation as the coin ratios above, but it is a game and it is what the rules say.
The implications under these two rules, as regards coins, are mutually contradictory. I see no way they can be reconciled. If you are insisting on a strict RAW answer, then, yes, it seems a mage can arbitrage the system, and with far more profitable platinum, even.
As a GM I would disallow this in a heartbeat. (That said, some people might find it interesting to work through the idea of a king or a wizard pumping money into the economy; but that is the sort of genre control I expect GMs to exercise and simply say, "I'm not dealing with that.")
Best Answer
Fabricate’s wording here is rather awkward; the original materials are both target and material component, are both converted into a finished product, per the rules of the spell, and consumed as part of the casting, per the rules for material components.
As written, you could actually argue that fabricate requires twice as much material as you need for the finished product, one to target and convert, and the other to use as material component and consume. If you accept this interpretation, then Ignore Components would eliminate the second set of materials needed for the component, but you would still need one set to target.
I’ve never heard of anyone running fabricate that way, and while I can almost buy it (fabricate is extremely powerful, after all; giving it a 100% up-charge might be better-balanced), ultimately if that were what was going on I would expect the spell rules to really explicitly indicate that. Like I said, no one seems to have come to that conclusion.
Which means that the consensus is that fabricate implicitly does some kind of weird conflation of target and material component. How that works is not spelled out by the rules, and is basically an unconscious houserule. Targets and material components are not normally the same thing and the rules don’t really specify what happens when they are—which means you could argue that yes, Ignore Components eliminates the need for the materials, which are both material component and target.
But I think a far more fair reading would say that even if Ignore Components eliminates the need for the material as material component, it does nothing for the need to target the materials, nor for the line that
Ignore Components doesn’t touch that, and should still be in force even if the material component aspects of the spell are erased.
Thus, in conclusion, my answer would be “No, you cannot use fabricate to produce goods from thin air with the Ignore Components feat.”
I would also just comment that I do not think a balance-based argument here holds much merit: this is an epic feat we are talking about; balance does not exist in the epic rules, and so there is no particular reason to expect balance from them here.