As for your analogy - a paper is quite literally a blank canvas. You can create anything that you can imagine, assuming your talents allow. Facebook, however, is not a blank canvas. Far from it. Facebook confines its users to a predetermined set of rules for their own benefit ($).
Edit: to elaborate on my last point - when was the last time you saw something truly incredible created entirely via Facebook? Something absolutely amazing that just blew your mind. Please let me know. I'm ready to be educated.