Okay, well, maybe not gangs, but gang-style behavior.  According to the Wall Street Journal, one of the most notorious sites for police calls these days isn't a bar, but kid-favorite, Chuck E. Cheese.  Apparently the "family-friendly" destination can bring out the worst in "mama bear" instincts.  The Journal reports on everything from disordely conduct to violent assault, most sparked by the moms on the premises.

In Brookfield, Wis., no restaurant has triggered more calls to the police department since last year than Chuck E. Cheese's.

Officers have been called to break up 12 fights, some of them physical, at the child-oriented pizza parlor since January 2007. The biggest melee broke out in April, when seven officers arrived and found as many as 40 people knocking over chairs and yelling in front of the restaurant's music stage, where a robotic singing chicken and the chain's namesake mouse perform...

Fights among guests are an issue for all restaurants, but security experts say they pose a particular problem for Chuck E. Cheese's, since it is designed to be a haven for children. Law-enforcement officials say alcohol, loud noise, thick crowds and the high emotions of children's birthday parties make the restaurants more prone to disputes than other family entertainment venues...

In Toledo, Ohio, four women were charged with disorderly conduct after a melee erupted at a Chuck E. Cheese's there last year. According to police reports, it started when parents complained to the restaurant manager that children were loitering at the drawing machine. The children were Barbie Clifton's daughters, then 14 and 10 years old. Ms. Clifton had come out of the bathroom when she saw a woman yelling at her daughters and her friend.

"I thought, 'Oh my God, what's happening here?'" says the 42-year-old stay-at-home mom. "Instead of [the woman] going to the parent or going to the manager, she was calling my friend and daughters all of those names."

That touched off a fight between more than 10 people, in which participants punched and screamed at each other. One woman removed the red rope that marks the entrance queue and handed it to another woman, who swung the metal clip attached to it at others involved in the incident.

"I thought they were going to start attacking me," says Sheri Kellar-Raab, the first officer who responded.