How often would you have sex if the only limitation was your own physical ability or needs?
For the guys, that means either a fully cooperative SO, or you have no trouble finding ladies outside the hobby, or your hobby activity is not constrained by budget or real life schedule.
For providers, it means you don't have an income goal you need to meet, or you have an adequate supply of clients, or you have a cooperative SO or see guys outside the hobby.
I'm guessing that most people don't really want to do it five times a day every day. On the other hand, I doubt that once a month is enough for many folks. How often would you want it if there were no constraints?