Real but rare? Who knows what started it all...I doubt it was apologetic dude bumping into the pusher. At home, bumping into someone, running to catch a subway and accidentally crashing into someone, or cutting in line, or many other things, doesn't go well. You hear, "watch where you're going." "I was watching where I was going." "You cut in line?" All of that showdown type stuff. Not usually the case in China. It's far too crowded. Showdown type stuff also means someone must lose face...

Most of the time, fights in China are;

1. 2 or more, usually more, beating up on one.
2. Gangs going at it in alleys and clubs.
3. Friends, acquaintances, or the like arguing, scuffling a little, and then having all of their other friends break them apart.

I've seen tons of the above. It all usually happens quick as too, no taunting. I can think of only one time that I actually saw a guy pushing another and taunting him like this. Rare for China, at least in my experience...Hilarious dialogue though...