@Mr_NutterButter Pay toilets stopped being common in the US after feminists complained about it. Apparently, even back when pay-toilets were (somewhat) common, urinals were still free, probably because you couldn't block access with a door, unlike a stall. But if that's the case, then just block entrance to the entire restroom until someone pays.

https://en.wikipedia.org/wiki/Committee_to_End_Pay_Toilets_in_America