Those kids are garbage. I'm sure the worker didn't come out of nowhere grabbing at them. He likely told them to leave, which began the altercation. As the locals said it's all a game, they chase you out, you leave, you come back later. Rinse, and repeat.
Fuck the head kicks, fuck spitting on him, fuck the kid pointing his finger, and fuck the dumbass filmer.
To keep things in perspective, imagine if this sort of thing happened every time a security guard or janitor kicked skaters out of a spot...