This is yet another insight into current culture. The guy got a bit perturbed at the idea. Perhaps the idea threatened him. Which is another insight. A guy with a bottle of water is not a threat. It's not paranoid to politely decline if you have doubts. Turn and walk away. But this guy reacted defensively, then aggressively, as if his fight or flight reflex had gone into fight. Perhaps because all that media he's consumed (and fed via government controlled education) has him convinced that if it doesn't fit into his accepted narrative, it's dangerous.

I see a parallel with the folks who confuse critical words on social media with actual bullying. You can walk away from FB or Twitter. No one can reach through the internet and kick your ass. Yet we treat "cyber bullying" as a grave threat, while we teach our kids to be victims of the real thing by telling them it is wrong to defend themselves. False equivalences lead to false realities, maybe?