Having experienced it once, my bet is the guy threw an object at his car in he, very stupidly, got out to confront the thrower.
From experience I can say you should not stop and you should definitely not confront them unless you have a death wish.
Way back in high school a buddy of mine got into a fight at a football game with a player from the opposite team. First thing he did was take off his helmet - the other guy kept his on.
Big mistake.
Reviweing the game films the next morning the coach played the fight over several times.
His advice - never start fist fight with a guy wearing a helmet, especially if you are not wearing one. I've followed that lesson for quite a few years.
“…you should definitely not confront them unless you have a death wish.”
Or a bigger, badder firearm. There should be a bounty paid for taking those types out.