I understand wanting weapons for a hobby, and I think that should be fine, with plenty of restriction. If you want an assault rifle, you should go through the paper work. (And have plenty of cash)
What I'm getting from Wolverine is that he wants them to available over the counter. For no other reason than why not.
Chances are you are pretty toast if you are dealing with multiple attackers anyway, an assault rifle will not change those odds. I don't have figures at hand, but I'd wager most crimes don't involve multiple attackers.