This only holds if there were only one bar that everyone went to.
I'm going to give you the benefit of the doubt and assume you really did miss my point:
Twitter controls access to a very large audience, only rivalled maybe by Facebook. If you get banned from Twitter, you can't easily go and use a competitor. If there were tens or hundreds of Twitters in the world, then yeah, the "being thrown out of a bar" analogy would hold.