As others have said, the issue seems to be the age restriction listed in the PF advertisement.

The game is rated 13+ in NA so if the content at the venue is appropriate for 13+, there's no reason to list it as 18+. You have no way of confirming the age of a player. There are children who act more mature than some adults and some adults who behave far more childishly than some children. Listing an age requirement isn't going to keep annoying people from showing up if they want.

It could be interesting to hear from RP venue operators who don't advertise an age requirement to see how many problems they've had because players who could be confirmed as being ages 13-17 showed up.