I came across this story on Google News a little while ago:
Apparently, while performing a song from their new album Wasting Light, Dave Grohl (of my favorite contemporary band, the Foo Fighters) caught somebody picking a fight in the audience.
Grohl stopped the performance mid song to curse out the man who started the fight and have him kicked out of the arena. "You don't fight at my show, asshole," he started saying, "I don't put up with that bullshit. You people come here to have a good time, and that guy can fuck off!"
A video of Grohl's outburst is provided below:
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