I'm sure it varies from event to event. But they have control over which ones they agree to do (for the most part). But since the end result is additional ticket sales, it behooves them to do as many as their schedule allows.
But I have to scoff at: the actuall performing is a huge time commitment. It's their JOB. Most days they are at the theater for a whopping 3 to 4 hours. Contrary to popular belief, they don't have rehearsals all the time. Yes, the dance captain can call them and yes the musical director calls music rehearsals from time to time. But there is an awful lot of down time. Understudies have more time in rehearsal than do the reg. performers.
However, many CHOOSE to continue to go to auditions, readings and classes but that is a use of their personal time.
If we're not having fun, then why are we doing it?
These are DISCUSSION boards, not mutual admiration boards. Discussion only occurs when we are willing to hear what others are thinking, regardless of whether it is alignment to our own thoughts.