I'm pretty sure it's one of the Universal Mysteries. And it isn't just guns. Near as I can tell, women seem quite convinced that men should only be allowed one of anything that they enjoy, at most. This includes tool, cars, anything that gets lumped (by women) under the general category of "Toys". Unfortunatley, it just doesn't pay to ask why this is, at least it isn't a good idea to ask a woman, but I'm pretty sure it's genetic. I'm also convinced that Murphy (as in Law) is/was a woman. After all, have you ever known a guy that was that contrary just for the sake of being contrary?
BTW, please don't let any women see this, my Karma is bad enough these days...
Dave