I like this explanation too. What's odd though is the other accounts of similar experiences at Paris McDonalds'. (Is it the same one?)

But it wasn't a random violent asshole. It was three violent assholes which doesn't seem random to me.

Actually Perp-3 wasn't violent, as far as I could tell from the story. I think he mainly called him "perpetrator" because he was close, stood around, didn't do anything and seemed to be okay with what happened.

And of the other two, Perp-1 seemed to have been the manager, while Perp-2 was a customer (judging by the shades in his hair, and the "meal" in front of him).

I'm guessing the customer felt paranoid from the camera and complained to the manager.

It only takes one random violent asshole in a position of authority to incite his underlings. That might not be the whole explanation, but the fact there were three of them doesn't mean much in a situation where one of them is likely to be in charge of the others.

That's because, like the majority of people, you are probably quite bad at understanding both randomness, and the normal behaviour of violent assholes.

Um, sir, I have more than a layman's understanding of randomness, thank you very much. This is Hacker News; all kinds of people post here.

I'm not even sure what you mean by "random" in this case; we're talking about one event. I didn't say anything about the distribution of violent assholes in McDonalds or France in general. It certainly wasn't "random" when the first violent guy brings over other employees who happened to also be violent. I don't know about France, but in the US, there are strict laws on what a commercial establishment can do to get someone off the premises. Now, mafia-run operations aside, most places would just ask you to leave and threaten to call the cops if you remain.

Was just meaning that randomness tends to be clumpy and that violent assholes are more likely to be violent assholes when there are a few of them around, so the fact that they were three of them does not particularly decrease the chance of it being a random incident in comparison to there only being one violent asshole.