Guns are tools for killing. Nothing else. Of course you can use a car as a weapon as well, but you can't use a gun in any other useful way than to threaten and to kill other beings. And there's no single valid reason why a civilian needs such a tool.
To be fair, a guy I know did
hunt down and shoot three chickens in his town for a large Christmas dinner he was planning. And then the Safeway employees explained to him that the chickens were already dead, and to stay the hell away from their store, forever