One thing is that you can get a cold sore from your Soppy Aunt Eidith smooching you when you're a baby or kid. It's not quite the same thing as "you have to be having sex to transmit it." And chances are, just about anyone you meet was exposed from a parent or grandparent, or other relative going smoochies on the baaaaby.

On the genitals, though, well... It takes a bit more "effort" to get it there in an innocuous sort of way, I guess. So there's the whole "OMG SEXXORS!" aspect to deal with.

My sleepy two cents, anyway.