Sept. 23, 2010 -- On Friday and Saturday nights, at an increasing number of malls across the country, teenagers are being forced to bring along the one person they'd most likely rather leave behind: a parent.

Dozens of malls now have what they call a "parental escort policy," meaning teens under the age of 18 have to be with a parent or guardian who is 21 or over to enter. Most shopping centers have these restrictions only on weekend evenings, but some keep them in place seven days a week.

The Mid Rivers Mall in St. Louis, Mo., started sending away teens at the end of May, and it has resulted in both more customers and sales. After a month, overall mall traffic was up 5 percent on Friday and Saturday nights, and sales were up 3 to 10 percent in all categories, including teen-oriented retailers, according to the property's management.

Last month, the Tri-County Mall in Cincinnati joined the list of malls with a teen escort policy, and Jesse Tron of the International Council of Shopping Centers said the practice is spreading, particularly with schools back in session and the mall socializing that comes with it.

"We're in a period of increased activity for this," he said. "It's cyclical. Throughout the holidays, you'll see new policies be enacted."

The gigantic Mall of America in Bloomington, Minn., was the first to ban teens who didn't have adult supervision, in 1996, according to Tron's group. By 2007, 39 malls had similar restrictions and by 2010, the number had nearly doubled to 66.

The impetus for these regulations isn't usually a specific incident, like a brawl. Instead it is the generally unruly, horseplay-heavy crowds concentrated in the food court and at the movie theater entrance.

Malls Find Banning Unescorted Teens Is Good for Business

Before Crossgates Mall in Albany, N.Y., put a teen curfew in place, it had become "a babysitting service," said general manager Joe Castaldo, with thousands of teen mall rats roaming around.

The Crossgates rule is strictly enforced, starting at 4 p.m. Saturday when it goes into effect. On a recent weekend, one embarrassed teen boy was escorted by two mall cops in Smokey-style hats to his mother in another store at 4:09 p.m.

The Atlantic Terminal Mall in Brooklyn, N.Y., is even more restrictive. It bars groups of four or more unsupervised under the age of 21. When five or more shoppers as old as 20 are found, they are asked to disburse into smaller groups or leave.

"The policy is that kids aren't allowed to use the mall as a hangout," said Joe DePlasco, a spokesman for the mall's operator. "We're concerned about the overall experience at the mall."

Shelly Mahon, a parent in Boulder, Colo., regrets the mall crackdown. She lets her 16-year-old son Blake go to the local mall a couple of times a month with friends.

"They go see a movie and walk around," she said. "I don't like them to be there for long periods of times, more than a couple of hours, but I think young people do need a safe place where they can go and the mall can be a safe place."

Lenore Skenazy, a columnist and author of "Free Range Kids: Giving Our Children the Freedom We Had Without Going Nuts with Worry," said it's a mistake to bust up kids' clans or restrict where they can go. She lets her 12- and 14-year-old visit stores in New York by themselves.

"My son is out right now group of his friends," she said. "He just called and they were all on the city bus together. We're always trying to atomize the whole world. We drive our own kid to school, and now a kid isn't allowed to have more than three friends. We're a better society when we try to do things more communally."

Social issues aside, Howard Davidowitz, a retail consultant, said that shutting out teens is good for business. Even though many of the mall's specialty stores, like the clothing retailer Abercrombie & Fitch or the costume jewelry store Claire's, send out siren songs for teens' to spend there, the department stores, which generally attract older customers, are more important to the mall. They bring in more business because they advertise and promote the center.

"There has to be a balance," Davidowitz said. "The problem a developer has is if it becomes a hangout, it becomes scary for older customer. That's the department store customer, and that's the anchor of the center."

Castaldo of Crossgates Mall said sales across his mall have gone up as older customers have felt welcome again, and now that kids come in with mom and dad's wallets. "Now instead of teens just spending $10 on something, parents are coming in with their credit cards," he said.

New Policies Chase Away Mall Rats

That's not to say there wasn't some grumbling when the mall first started to turn teens away in 2005.

"I did get a few negative comments," Castaldo said. "It's unfortunate that there are a lot of good kids out there, but we didn't want to single anyone out. My own nephews were upset that they couldn't come unchaperoned."

Skenazy says they should be indignant.

"They're treating 17-year-olds like they are babies who need supervision or juvenile delinquents who should be behind bars," she said. "There's a lot of self-fulfillment in that policy. The less chance we give them to prove themselves worthy of our respect, the less likely they will."

Part of the reason teens are now able to converge en masse at the mall—instead of simply running into a friend or two there—is because it's never been easier for them to tell each other where they are, using their cellphones, or social media like Facebook, Twitter, and Foursquare.

Danah Boyd, a social media researcher at Microsoft Research New England, said "there's no doubt they use the Internet to tell their friends, 'Here's where we're doing and when.' Kids show up at the mall and announce on Facebook, 'Hey, everyone's here and you should be too.'"

As long as -- at least in some malls -- they're 18.