My wife is one of those people who always carries a pen (plus a small notebook) and while she it happy loan a pen to someone else, she cannot understand why people don't have pens on them.
It's rubbed off on me although I never have the forethought to stick a pen in my pocket - I now have a 3" Space pen clipped to my keyring and I'm more likely now to jot down things that I never bothered before.
I'm quite happy to lend it out but maybe that's because the cap stays firmly on the keyring :-)