In the same way some try to sell here now and then reddit or Twitter accounts, for example, they can try to sell bitcointalk accounts on other bitcoin-related social media platforms (other forums, discord, telegram channels, whatever). Probably some even do that (i.e. right now) to try to go under the radar, I don't know. But the (bitcoin) world is bigger than just bitcointalk (although most "places" may not deserve attention, this is still a reality).