You ever wonder why one-person plays got so popular? Sure, they're the ultimate vehicle for an actor, and, in fact, several of the best plays I've ever seen have been for one performer. But it sure is cheaper to pay one performer than ten, isn't it?
I was sitting in the Los Angeles Farmer's Market recently doing a script consulting session, when the subject of multiple casting arose. It's hardly uncommon in these days of tight theatre budgets.