Quote Originally Posted by Mirage View Post
Yes, there is a reason. Developers won't bother spending a lot of extra time programming in support for something that most players won't have access to.
I really doubt that keyboard and mouse support would be budget breaking when it comes to developing a game. If more console FPS's supported it, I bet you'd see more people buying a USB keyboard and mouse for their consoles to be honest. I know I would, and maybe then I'd actually buy a few more console FPS's.