A lot of it is buying the illusion/experience. They are helping that girl get back into veterinary school or are virtually rubbing her clit by making panties vibrate or whatever.

Also, it is generally not the same whale every night. Sometimes it is, but most models have a set of regulars.

And the other aspect to remember is the good old audience plant. Think of it like starting a hype train on twitch or getting the meter most of the way to the exposed titties goal or whatever. The idea is a friend or site employee uses cheap tokens to encourage others to use real ones.