Well yeah, you've got a point there. Then again, I would probably be publishing it for the sake of saying 'Hey, I wrote a book and it's on the market!' I mean seriously, guys dig chicks that write.
Besides, even if there were a decent demand for fantasy books, I still wouldn't make it my primary money-making tool... because then it wouldn't be writing for the sake of writing. I would be forcing myself to come up with new ideas and that kind of kills the process for me. =/
But yeah, role-playing is escapism for me. I wish I had more of your practicality, though.