Thats not how supply and demand works, any supply and any demand affects prices, and me growing food affects both, even if i dont cover my entire demand. I can and do grow a surprising amount of food. I cant however raise cattle, or pigs, and could only reasonably raise chickens for eggs, not for meat. Because anyone, me, other folks, and small scale farmers all can produce more supply with produce instead of meat given the resources. Its not a cornerable market