Good point but there would still be a surplus by just breeding on their own. Look at deers for instance. We don't breed them they breed by themselves and every now and then theres a surplus and open season is declared to decrease the population. I don't like it but I see that it is necessary. Just like war. It's necessary to decrease the human surplus population.
I hate the fact that animals can't protect themselves. That they are at the mercy of humans to do what they wish with them. Its not fair but its how the world works.