The thing I laugh at is "those aren't designed to kill." Well cars aren't meant to kill, that's a given. But how many people die per year, percentange-wise and number-wise, from cars than they do from guns? How about me selling a kitchen knife that's sole design purpose was to cut through flesh, whether it was people-flesh or animal/plant-flesh? Can I not sell a walkie talkie either? I mean shoot, those were designed to be used as a communication device for the military, which kills people! Or even a microwave, that was accidentally discovered trying to design a radar to find planes so you could shoot them down! People are stupid, they blame tools for a crime and not the person behind said tool.
It all boils down to the fact that most people can't, and won't, take responsibility for their actions. It's always someone else's fault.
"An armed society is a polite society. Manners are good when one may have to back up his acts with his life."
- Robert A. Heinlein