What I do see, are people wanting to take part in roleplay events so that they CAN play someone other than themselves, hence the high proportions of warriors and wizards. Playing a character who is subservient could quickly lose its appeal - who wants to turn out on a night to feel controlled and oppressed? - be honest, would you really? It sounds masochistic to me!
I've done an event where the organiser said you can come as literally anything you want - by your logic this should have been the best event ever?
Anyone else out there want to pitch in?