Do you really want a system that looks over your shoulder and decides for you what you can and can't have?
Yes I agree, certain things need restriction. Who are you going to hold responsible for the actions of someone intent to do harm? If not the person themselves? Where would that end? I know its been said, but, a drunk driver kills someone. Do we hold the people that built the car responsible, or Jim Beam? or maybe the guy that drank too much and got in the car.
There are many things out there that do harm and yet are legal, so yeah its the responsibilty of the owner. Cigarettes are still legal and they KILL tons of people and cause all kinds of problems. What do they do about that? They try and educate people. Same with drugs....they kill, they are illegal....we educate.