Bully bartender

So at my local pub that we hang out in all the time- there is a bully bartender who I finally got into it with. Our friend and this bartender don’t get along. Our friend is seriously a really nice human. He’s older, 55, has a good job and is very intellectual. I don’t know exactly what the beef between them is but apparently when this bartender is on shift, my friend can’t be there.

So the other day we are hanging out and in comes the bully bartender for his shift. 2 seconds later the waitress brings my friend his check- slams it down and says “you gotta go”. He had already packed up his leftovers and had half a beer to finish.

2 more seconds later the bully shouts loudly “get out of here, time to go!” Literally across the bar in front of 20 people. He was just finishing his beer that he PAID for. So I defended him saying he was finishing his beer and would be going after. The bartender got irate and was screaming at me (I’ve known him for 2 years pretty well). He shouts “no one likes him! He needs to go now!” And I said “we like him, he’s our friend and he’s not doing anything wrong. He paid for his beer and he should be allowed to finish it”.

Bartender looks like he was about to have a heart attack. Screaming and shouting now at me!

My question is- I know the bar owner well, should I tell him about this incident? Such a disgusting way to behave and treat customers. Literally this guy was doing nothing wrong, wasn’t drunk or loud. He’s such a nice guy! The bartender always plays horrible music during his shift so loud and you have to beg for service. He’s the worst bartender ever!