Dude you can do whatever you want. If you want to start something that's readily copied, go ahead.
But if Godzilla steps on you, dont act surprised and dont expect a lot of sympathy.
But if Godzilla steps on you, dont act surprised and dont expect a lot of sympathy.
In Zynga's case for instance, FB was pretty darn dependent on the advertising $$ Zynga paid them (among other factors). In Instagram's case, I believe that Facebook wished to avoid pumping up mobile app traffic that quickly. Etc.
Obviously, YMMV. The strength of the answers varies wildly, and startups often lose the bet -- even when the bet was calculated well. C'est la vie, et c'est la guerre.