Many vegetarians have chosen meat free diets as a way to avoid the environmental degradation and gross misallocation of resources, such as grain and water, associated with the CAFO’s. Not only do those problems fall away in grass based systems, but many become benefits. For instance, pollution from manure runoff in massive feedlots threatens water quality and ecological biodiversity. On pasture, however, manure serves to fertilize, creating a more resilient and diverse plant and soil ecosystem.