What's wrong with being anti-gun?
It demonstrates basic insecurity, exactly the way being "anti-hammer" does.
“A fear of weapons is a sign of retarded sexual and emotional maturity”
Sigmund Freud
It also demonstrates the triumph of fear over intellect.
“Most people do not really want freedom, because freedom involves responsibility, and most people are frightened of responsibility.”
Sigmund Freud
Being "anti-gun" also substitutes the rare case of being harmed for the not at all rare case of being saved from harm. Someone who is "anti-gun" would laugh at the idea of being "anti-fireextinguisher", since they acknowledge the benefits of having one, and yet a fireextinguisher can easily be used to kill.
Just like a hammer. Bang bang, Maxwell's silver hammer made sure that she was dead. Ba-dum dum.