Anyone who plays RTS games (or RPGs) on a serious enough level to need quick access to keyboard shortcuts wouldn't even consider trying it on a handheld device - many of them complain when playing on certain desktop keyboards. Nobody's going to play StarCraft at high-speeds on any handheld device. For the rest of us who would just play it (or most RPGs) at a normal pace, the touchscreen is a perfectly good input device. The keys are still accessible for certain useful shortcuts (I for inventory, C for character sheet, etc.). (I don't know any StarCraft key shortcuts, as I don't really play SC.)
EDIT: When I said "require", I MEANT "require". FPS games need the keyboard so that you can control character motion, because the mouse only controls viewing angle. For any RPG/RTS that I've ever played, it's fully playable with just a mouse. StarCraft worked decently on the N64, and that didn't have anything remotely close to a keyboard.