I think this “funny” business may become a regular feature.
I completely understand the impulse of not letting your kid wander into the men’s bathroom all by himself. The men’s bathroom is an eerie place to me too – like Easter Island with plumbing. I’m one of those sexist women who sometimes wonders if guys have penis-measuring contests in there. No child should be exposed to that until he can chug a whole can of beer.
However, I see enough urine on the toilet seat at home. In the outside world, the ladies room is a sanctuary (well, sometimes it’s not, but whatever). You might say, “Oh but Natalia, what about the transgendered?” I say, “I’ve never met a trans person who pees on the seat. Sure, they may be out there, but they’re in the minority. So there.”
So if your kid sprinkles on the toilet seat, clean it up, don’t just giggle and walk out (I’m talking to you, movie theater lady). Especially if the majority of the other stalls are occupied. Especially if you don’t want terrible karma stalking you like a black cloud or a pervert for the rest of the week.