I agree, but the core product here is the Game itself and not any of Facebook's functionality. Sharing was only an added benefit. If you recollect, the original

I agree, but the core product here is the Game itself and not any of Facebook's functionality. Sharing was only an added benefit. If you recollect, the original game was hosted on Zynga's main website (where you could go directly and play if you wanted) and it was served via an iFrame on Facebook's app (this was before even Facebook came up with the app rules of having an iFrame). So, if Zynga, for example, had built a messaging service that was completely dependent on just Facebook's API, like the Start-up in question, I think they would never have seen the money they saw. I agree, 'never' was perhaps too strong, maybe I should have said '99% of the times'.