Ladies Night
There's a few things for us to take away from this thread.
1) For sanctioned events, think “inclusive, not exclusive”. Your venue - i.e., the store - may disallow service to a customer who has proven problematic in the past. However, you (Judges, TOs) must not exclude people, esp. not on the basis of a “protected class” (race, gender, etc.)! You probably could charge different entry fees - but that's a question for the TO to discuss with their WPN rep, *before* trying something.
2) for non-sanctioned events, the rules are now entirely up to the Organizer. However, one unwritten rule that I personally, and others - including some wise and experienced folks at Wizards of the Coast - will recommend: do what your customers want. Do women want a “Ladies' Night”, for Magic: the Gathering? Do they want a lower entry fee than what the men pay? Or, do they just want what most of us want, at any given moment: to be treated fairly and equally? As I said: find out what your customers *really* want, then do that.
I'll also point out that a lot of really bad marketing ideas have been tried over the years - but rarely are any of them based on consensus customer feedback.
d:^D
P.S. - store owners - TOs - should know who their WPN rep is, and they benefit from cultivating that relationship. It's not necessary for us, as Judges, to have any clue who or what a WPN rep is … some of us perform both roles, but the rest of us can seek bliss in our ignorance! :)