For the ladies it provides another means to screen clients. Also gives opportunity [ in some cases] to get a sense of a gents persona , likes, dislikes,patterns etc...before you book with them.  I really think it offers another level of safety.

For the gents if utilized correctly it limits risk as well as wasted $$

I can't imagine why any serious hobbyist would not take advantage of this valuable tool.
Nor do I understand why the ladies would not consider VIP as a valid cost of doing business