The low prices make it hard for small farms or homesteads to compete...If you got like a million chickens housing and feed costs per chicken go down, low margins and possible government subsidies do the rest...
Without that, we all would probably pay a lot more for food stuffs ....
The possibility of unwanted chemicals or hormones in our food is a bit more of a concern, we had a big scandal years ago where animal feed was contaminated with machine oil so we had eggs with dioxine...It caused some heads to roll and and led to a lot of new regulation and inspections
In Britain years ago researchers found that some fish were affected by residue from contraceptive and other medication that did not get filtered out by water treatment plants.... (yea I know, I watch too many documentaries ;-)
Have you thought about sprouting grains or sunflower seeds? all it takes is a number of plastic buckets and water to triple your feed in weight ,