I agree and I think professionals in most industries are frustrated with their customers as customers are becoming more educated and discerning. This seems reasonable and inevitable. From freelancers to fortune 500s like General Mills they're basically saying, "Why won't people just take what we give them?"
I think the answer is actually pretty simple, the producer (be it food, software, hardware, home goods, etc) often compromises quality, security, health, etc for the sake of a little more profit.
To some degree, they're right... they are usually the expert and what they make will be better than what the customer wants in some ways (ex. longer shelf life). But of course consumers are more aware of this dynamic, and they're pushing back for more of the quality, health, etc.
So ya, I agree... the market should decide a lot of where that line will be drawn. Many of these ingredients may not be proven to be unhealthy, but I think people are starting to realize how much we also don't know. While sensitivity to a certain ingredient may not have been found in a 2,000 candidate study, maybe it does affect 1 in 2001. If there are better alternatives, then that might be a worthy exploration. The producer who finds a better alternative will have a market advantage.
Of course, where it is discovered that an ingredient or a process is high risk (such as trans fats) then I think it's reasonable for the FDA to regulate it.