If this is true, we should as a matter of principle, and not just personal self-interest, avoid buying products produced by large corporations as much as we can, preferring locally grown or small company produced products. When we do buy from a big corporation, we should buy organic products because at least then the earth will have been treated better.
If we do not buy corporate products whenever an alternative exists, we accomplish two things. First and most important, we reward those who act appropriately in their production of food. As we do, they prosper and are encouraged to continue, others are encouraged to enter into business in the same way, and the earth as the foundation for the abundance we see around us, is helped.
Second, we give that much less to the sociopathic enterprises who are doing such damage to the earth and all life within it. If enough of us do this, we will help create a shift, but at the moment, that is a long way off. The first reason: rewarding those who act appropriately and so honoring that which we consume is enough.
What if a large corporation produces organic products? Buy them so long as there is no local equivalent. But we will have a chance to bring agriculture into greater harmony with a Pagan sensibility only when it is overwhelmingly dominated by human beings capable of taking an ethical approach to what they do.