A gang calling itself the "311 Boyz" either beat up one another or pummeled strangers, including girls - all for the cameras.
But, as CBS News Correspondent Lee Cowan reports, shooting their fights also shot them in the foot.
Now charged with a litany of felonies, their attorneys have to defend not only their actions but the tape.
"They didn't think it was stupid at the time," says attorney Bucky Buchanon, "They thought it was macho."
This is what "macho" got Tanner Hansen. He says he was trying to flee one of the "311 Boyz" beatings, when a rock came through his windshield.
"The rock had hit so hard that it crushed every bone on the left side of his face, his nasal cavity and his eye socket," says his mother Carma Mahn. "They didn't care if they wounded, they didn't care if they killed. To them, it was almost like a growing thrill."
Capturing a violent thrill on tape is nothing new.
Teens in Jacksonville, Fla. recorded themselves trashing million dollar homes. Teens in Los Angeles were laughing so hard they could barely hold the camera as they shot people with a paintball gun. And then there was the act in which one teen videotaped another as he sucker-punched a complete stranger.
But what the Vegas videos bring into focus is a disturbing new trend. Not only were they just trophies of sorts for the teen's bad behavior. But in this case, the peltings were also meant for profit.
Fueled by backyard wrestling tapes and reality TV, lawyers say the teens simply saw dollar signs.
"I think they thought, 'Well, let's get in on the action, let's do some violence, let's do some staged fights and some real fights, let's videotape it and see if we can make a financial bonanza out of it,'" says Buchanan.
Clinical psychologists like Dr. Ken Druck aren't surprised.
"I don't know why it's a shock to us that these kids would try to find a way to turn violence into entertainment," says Druck. "It's all around them."
Remember the "Bum Fights" videos? Those were made in Vegas too.
"The precedent for somebody making money, being successful, and doing this was there," says Druck.
In the end, their tape may well lead to their convictions. It's the best evidence police have.
But it's also another sign, some fear, of a growing detachment between reality TV and just plain reality.