I know your pain. My wife and I just returned from the same experience. Twice we were paired with relatively inexperienced divers. On those occasions we ended with between 1500 and 1800psi - way to much air! Next time - we are going to establish up front in the dive plan how they deal with this issue. We too are used to diving our own plan. I think part of the problem might be that in Playa they tend to see divers with much less expereince than in Cozumel. In Playa is really is "group" diving.