Why aren't there any J.O clubs for women?

All across the country,there are what is called "Jack Off",or J.O. clubs.Members gather around naked to pleasure themselves in full view of each other.Mastrubation or even mutual pleasuring is allowed but generally nothing beyond that.But I've noticed that all of the clubs Ive heard about are ALL male-only.I can understand why they wouldn't make them co-ed,but why haven't I heard about even ONE such club that exist just for women?I know that women like to pleasure themselves just as much as men!