Why would you pull a weapon when everyone is running from you? You do that when you actually feel threatened. Also, I'm sorry, but slapping someone in the face is still hitting them...especially considering that he has already thrown numerous punches at people.
I'm sorry that the guy who knocked him out is not considered "manly" enough to some of you...but that isn't the point. The point isn't to look manly to people on the internet, or to get into a fight for ***** and giggles. The point is to stop some idiot from committing assault on other people as quickly and cleanly as possible.
If you want a fair fight you get in a boxing ring. If some idiot on the street is attacking people you put him down with as little danger to yourself as possible. It's really that simple.