I really don't think you can connect this to hunting. People back in the days hunted deer etc. to survive, you don't need to stick two pit bulls into a ring to kill each other to survive.
You don't just go out a shoot a deer for the hell of it, that's inhumane. Usually when you hunt you want the meat, or the body, and usually all you need is a shot, which I would consider humane. Beating it, torturing it, and mutilating it just for the hell of it is not.
What Vick did, throwing dogs into a ring with the intent of just watching them kill each other just for the hell of it is inhumane, and yes he should be punished for it.
I really don't think he is going to do his full sentence either.
-Justin