Because most people do not grow their own food, their food must be grown for them. Because one person with hand-tools can only grow enough food for several people, and because so many people are not growing food, food is being produced with the assistance of polluting machines, poisons, chemical fertilizers, and non-replenishing water sources.
People living in the vicinity of farms that use poisons are being directly poisoned and even government health organisations will admit that children are getting leukemia, cancer, and allergies from exposure to these poisons.
To support and sponser chemical farming by buying chemically produced foods is to be a contributer to illness in others. We do not want to act in such a way as to to knowingly inflict suffering on others. This is part of living nonviolently. We must have the courage to grow our own food.