Example:
Chaturbate Karynaandpaul - xHamster.com
For the performer, it is basicly impossible to control where there stuff ends up.
So it is only natural, that they are trying to protect their work. And for a lot of CB models, it would also be privacy issues.
It is a difference, if an illegal recording hits it good on the tubes and recieves hundreds of thousands of views on day one making them nothing with an extremely higher chance of mom and dad stumble upon it, than rubbing one out to a few hundred audience or even private show.
Just trying to explain where they are coming from.