Why are you talking about "ethics" and promoting stereotypes when talking about classes. Thats like saying everyone should buy Hondas, because anything else is promoting stereotypes. Er...no.
This is just an additional choice, like "advanced handgun techniques" vs. "advanced hadngun techniques in a home environment." They are equally valuable to those who take them, just offer a different flavor and choice. There's no ethical issue here unless your intent in teaching the class is to be creeping (as the daughter says) on the the female participants.
EDIT: I'd offer a class for "gay folks" if there was a market for it. I don't see an issue in that either.