i suspect the concerns are, if your food is killing people or making them sick:

1) how big is the fallout,

2) how insulated from repercussions are you?

if a small local farms food is making people sick, it will only be a few people and word will spread.

a small local farm could more easily go out of business from just a few sick people. the market functions correctly at that scale. if a major corporation does it, the market does not function anywhere close to the same efficiency and the fallout is 1000s and 1000s of people sick or worse.

i think what many are arguing is that the responsibility should scale along with the possible impacts.