I guess the language barrier and kinda not understanding what was going on played a part in the Czech guys' trying to intervene, but even after the French parents explained (in English) that their kid had been misbehaving, they still kept after them. It wasn't like they were beating the kid senseless, just scolding him and holding firm to his arm and not letting him get away from the reprimand. I guess that's just not OK to some folks.
Personally I think they shoulda took the stick and popped him with it a couple times but that's just me. Were it not for not speaking French, I'd have told the kid to cease and taken the stick away if he'd gotten close enough. That and getting into an altercation in the cemetery would be inappropriate. But the issue was swiftly rectified by the parents, at least.
My sister and I were always super well-behaved outside the country as kids. Our parents would've disciplined us if we hadn't been. They didn't need to.
But oh boy oh boy that one French kid was nothing compared to all the Chinese kids coming through the Prague airport. And in the British Museum the next week. Waiting for our baggage carousel to start circulating and there's this unholy rush of noise and a couple dozen Chinese kids with two ineffectual adults come blitzing through the place, climbing on shit, riding on the carousels, riding on the baggage carts.
In the British Museum, this was at the height of the "selfie stick" craze. The Museum had signs saying no sticks. In multiple languages. Apparently the Chinese schoolkids are either illiterate or are just little sharts, 'cause half of them had fully-extended sticks without even their phones on them. There were hundreds in there that day, multiple school groups. All of whom were either running around like monkeys or sprawling on the floor like dead monkeys so everyone else including elderly people had to step over them like it was some minefield in the Korean War. I don't remember what we were looking at, some artifact from Sumeria or something in a case, but these two kids come sprinting through the crowd, knock my mom (who at the time was around 71) to the stone floor and against the stone case, and ignore her. West Country-sounding bloke grabs them both and starts telling them off for running, waving their idiot sticks around, and knocking an elderly woman to the floor. Of course they just looked at him like he was speaking gibberish and ran off soon as they could. Mom was fine but damn, it was a shame seeing the museum like that. I've seen heaps of Chinese tourists before, but never kids that ill-behaved. I'm sure they didn't remotely speak English, so that was their "excuse" for not having to behave like civilized people.