I think you are setting up a false premise here.

There are many people (including me) who have been using the internet for a very very very long time and don't see facebook as the internet even though we use it.

And I can see that I get quite a few sign-ups to my service that way.

Also the problem is not as much whether people use it for traffic generation. The problem is when they only use it for that.

I am actually beginning to consult my clients on how to build their own digital ecosystems so that they don't leave all the value inside the gates of facebook, twitter etc. but rather attempt to get the value transfered back inside their own ecosystem.

Once you start seeing it that way things start to look very different.

I made a longer argument about it here:

http://000fff.org/how-to-think-like-facebook-and-twitter/