I can't even count the times I've heard of someone getting into a bar fight and not being content to get their ass kicked "like a man" proceed to get a gun out of their car and shoot like six innocent people trying to get back at the person who did the ass kicking. It's a cultural thing methinks...
I can't even count the times I've heard of... Probably because that count would be exactly... zero . I have over 60 years of criminology data and yet cannot find one case that meets your stated criteria (bar fight or any other collection of strangers resulting in more than 2 fatalities or 3 wounded).
1 dead 2 wounded: http://www.azfamily.com/story/37585825/police-investigating-...
1 dead 2 wounded: https://www.azcentral.com/story/news/local/phoenix/2016/10/2...
and that's just Phoenix.
Hold on...found a 6 people shot one too: https://www.click2houston.com/news/6-people-shot-after-fight...
Don't think your criminology database is all that comprehensive...
--edit--
Actually, just up the street from the first link I was in the parking lot of Kitty's Bar calling into dispatch (was working for Sunrise Cab at the time) and this "individual" took 3 or 4 steps into the street and unloaded his handgun in the air. Me (being me) looked at this "individual", who's 30-40 feet away from me, and see he's not shooting at me so go back to what I was doing and was like "whatever".
Only thing I can think of is he was either mad at getting kicked out of the bar or perhaps wanted the traffic to stop for his jaywalking, dunno? Of course all my later calls were in the area the police were conducting their manhunt which was a PITA.