"The mere fact that a market exists for a product, does not give a green light to any company to produce that product in an unacceptable way having scant regard for the health and safety of its employees or those who consume the product."
I agree 100%. However most farmers are not companies, and are extremely good custodians of their own land, and are among the most efficient food producers in the world. Farmers don't want to rape the land, because, first it has to sustain them, and second they want to pass it on in good condition to their successors.
What you are talking about is companies that are irresponsible. That's a different ball game altogether.
What I find so hypocritical is, for example, a recent coal-mining protest where the protestors lay down in front of a coal train. When they got tired of that, they went home and turned on their electricity.
If they did something constructive towards alternative energy, then that would make sense, but stopping coal trains, I don't think so.