Shot size restrictions are for safety. A camoflaged hunter taking a load of #4's from a yahoo shooting at his deke is gonna get pretty hurt, but pretty hurt hunter is better than pretty dead one. Of course you can die from #4's, but you have a better chance. And before anyone says, yeah, that will never happen, it has and does happen more often than you think. Someone took a shot at my friend's B-Mobile last year, and luckily my friend only got peppered with bark from the tree that got hit and didn't take any pellets.