Why does Jakes overload his cart with corn? Do you agree with his reason for doing it? Would his argument work in other situations?

It was actually the foeman that was a cruel taskmaster. Jakes "often said that it was more than [Beauty] ought to take, but the others always overruled him." It was totally not fair to burden Beauty with more that the horse could handle. This is no valid argument to cause suffering to an animal.