So, what would you have done had you arrived and he was out due to illness or something not scheduled? I understand buying tickets to see a certain performer, but there is never a real guarantee they will be performing. People have things come up, people get sick, etc. I understand in this case it's fairly specific because Alex does have dates he doesn't perform, but still - things do occur and events like this happen. I don't know whether he'll be performing that day, but like any performer - things happen.
"Anybody that goes to the theater, I think we’re all misfits, so we ended up on stage or in the audience.” --- Patti LuPone.