As the previous poster said, depends on the company.
Chipotle actually tries to source their food as much as possible from farms that use sustainable practices and feed their cattle grass etc. They just went through a major re-tooling of their store in Charlotteville VA to use the pork from Joel Salatin, the famous farmer from Food Inc. So some companies go to great lengths to help build good environmental practices.
Others could care less and maximize profits over everything, whether it is the environment or safety of workers, etc. If you look at the recent case of Massey Energy, a company that has been pursuing the bottom line at the expense of its workers as well as the environment around their mines, you can see the different outlook they have on the environment and the practices they undertake to maximize profits.