Well, overkill for home defense, hard to say what is. A shotgun is probably more damaging to a person than a 9mm pistol can be, pistol's probably best for that purpose anyway. As for hunting, isn't most assault rifle ammo not suited for that, not due to obliterating the animal but being too weak (have heard a .223 round isn;'t enough for deer hunting) ? Not as if you're blasting them with .50 rounds.
Most do seem to argue for a total ban as they just don't like guns. Laughable idea to implement in the US now, though.