I'm not sure I agree with your assessment of the type of people verified on twitter. I mainly use twitter to follow comedians, and most of them don't make a ton of money (surely not enough to afford "a thousand bucks a year" -- one of my favorite comedians working today has said publicly that he made all of $16k in 2015).

And a few have become the victims of imposters who attempt to disrupt their careers by taking on their identity and messaging comedy clubs or TV networks or whatever. I don't think they are an untapped revenue stream.