I think there is a huge difference between the present system of legalistic lying through omission and an unregulated food market. If there is a whole government system there to assure the public that everything is safe and hunky dory, it is open to corruption from within the system, as people manipulate regulations to hide the truth from the public.
Whereas in a free market, it is known by the consumer that they are the ultimate authority as to what is safe and not safe to eat, and competition will ensure those who lie and cheat will be forced from the system by attrition by those who do not.
Will some people be harmed in this system? Sure. It happens, life has risks. But I've never heard of a system that suffers from a smarter and more aware consumer.
I think you are a bit ignorant of how people act.
There is a reason the USDA and FDA exist. Look into history, and see what was being passed off as food before they came into being.
A “Free Market” doesn’t really exist. For one thing, the meat packers would start adding a lot more extenders (non meat products), and stop the inspection process. And they would have no reason to tell you or anyone about it.