Erm... what's so wrong with it? That's the type of roleplaying that I do. It's not just for "losers" or "people have too much time on their hands". Just because you think it's odd, doesn't mean that it's not popular.
Journal-Roleplaying, without RPing on AIM, isn't very time consuming. You type up a journal entry...then, go about your life. Or lack thereof .
For quite a while, I was RPing as Stevie, but right now, I'm not doing it that much. Mainly because he doesn't have an SL. So, now, I'm kept busy with X2 chars.
EDIT: Okay, I just noticed something... most of them, ie the ones I saw, didn't have any friends. So, that means they're not part of a community of Roleplaying. Erm... so, if they're just Roleplaying all alone and by themselves, then yeah... that's just sad.