Demi Lovato took a page out of Simon Cowell's playbook ... kicking a pair of 'X Factor' contestants off stage today for rapping about smoking bath salts ... TMZ has learned.
Sources on set for 'XF' auditions in Greensboro, NC ... tell us the two guys laid down a rap that included the line, "I'm high on bath salts."
Apparently most of the crowd didn't hear the lyrics, but Demi did -- and as soon as the duo finished she furiously scolded them, saying ... "It's really inappropriate to rap about drugs in front of kids."
Demi did a stint in rehab in 2011, and has admitted to using drugs and booze when she was underage -- so, it's no wonder she went off on the clowns.
We're told the audience agreed with Demi, and booed the contestants off stage ... and they were not judged for the competition.
I know like...why? but what she did was great! I really think she's going to surprise people when the show airs, she seems to be handling the judge gig she's been given very well!
A reply there to someone who says everyone should stop acting like this makes her a saint(I see his point though):
If it ends up on air, you will see why it is made out to be a big deal. These guys were acting like they owned the place claiming they had fans all over and tons of hits on their YouTube videos. They needed someone to get them off of their high horse, she just so happened to be the one to do so.