I can only speculate, but considering the nature of the event, the fact that the event is on a non-RP server and is welcoming to all players (and not just those who RP), and is not (at least where I can see) explicitly stated as being an RP event (just that it could be if people wanted to show up and RP there), the reason for the gender confirmation would be for those who do not RP and are looking for companionship of some sort, would be my guess.
Which wouldn't be a bad thing at all, I don't think.
Which wouldn't be a bad thing at all, I don't think.