Anyone ever used this or heard it used IRL?
I’ve never heard it used IRL, only in cartoons and old movies. (Someone uses “mac” when they doesn’t know the name.)
I’ve used it a few times just for kicks. They typically have a quizzical look as though to say “Why are you calling me ‘Mack?’”
I married into a family of Gaelic extraction. A lot of my wife’s relatives are nicknamed “Mac”. But I don’t recall ever hearing it used generically.
Old Joke:
“Hey Mac! Can you tell me the time?”
“How’d you now my name was Mac?”
“I just guessed.”
“Well guess the time.”
Wouldn’t that be just like calling somebody ‘buddy’?
“Hey, buddy! You hit my car!”
It doesn’t mean they’re your buddy. No, sir.
That was a well-plotted piece of non-claptrap that never made me want to retch.