The price of these printers has dropped by over half in a year. Won't be more than a couple of years and they'll be commonplace and anyone will be alert do this, or print knives etc.
The guys a chump, but not the only one over there. Since its invention the motor car has slaughtered far more than the firearm, but seat bets still aren't legal in most states. While its a rum affair in not going to sweat over that in particular when there are many much more likely and prolific methods of killing people that still aren't properly regulated.