Louisania shooting movie theater security
Police stand by at the scene outside the movie theatre where a man opened fire on film goers in Lafayette, Louisiana July 23, 2015. Reuters/Lee Celano

NEW YORK (Reuters) - American high school students walk through metal detectors each day. The Metropolitan Opera in New York searches the bags and purses of patrons each night, and air travel involves long lines and security checks.

But the nation's movie theaters are unlikely to introduce such stringent measures anytime soon despite the latest shooting inside a Louisiana multiplex, security experts said on Friday.

Cost, staffing and the turn-off factor to what is supposed to be a fun night out will likely deter movie theater chains from adopting airport-style security, especially at a time when attendance is dropping thanks to the lure of online streaming, YouTube and video on demand.

"Owners do not want the experience at their theater to be a negative one, and going through a metal detector and having their bags checked would become a big inconvenience," said Tom DeLuca, president of New York-based Global Security Services, which has provided armed security personnel to some of the biggest movie chains for 15 years.

"My gut tells me that people would say 'Why am I coming here? It must be dangerous. I don't want to bring my children to this theater, so we'll go somewhere else,'" DeLuca said.

DeLuca's company was fielding calls from movie theater owners on Friday following Thursday's shooting, in which two people were killed and seven wounded when a 59-year-old man opened fire during a screening of comedy "Trainwreck" in Lafayette, Louisiana.

It came three years after 12 people were killed at a cinema in Aurora, Colorado, during a midnight showing of "The Dark Knight Rises." Last year a man annoyed by a texting movie-goer gunned him down inside a Florida movie house.

Movie theater chains barred the wearing of costumes and masks to conceal identity after the Aurora shootings and said they had stepped up security generally.

Southern Theatres, the privately owned theater company that operates the movie theater in Lafayette where Thursday's attack took place, could potentially face legal claims over its security.

A federal lawsuit by more than two dozen Aurora victims or their families is set for trial in July 2016 to hear claims of lax security against theater owner Texas-based Cinemark USA.

DeLuca said movie owners were quickly on the phone on Friday. "We already have had some calls today. They are asking A-Z. One of them is asking for an opinion. Another one is asking whether they should reconsider the metal detectors and bag checks. Ultimately I don't think they will ever get to that," he said.

Major chains like AMC Entertainment Holdings Inc's AMC Theatres, Regal Entertainment Group's Regal Cinemas and Cinemark Holdings Inc did not return requests for comment on their security measures. Southern Theatres on Friday offered thoughts and prayers to the victims in a statement but made no further comment.

On a day when the S&P 500 <.SPX> fell 1 percent, AMC was down 3.6 percent, Regal down 1.5 percent and Cinemark down 1.3 percent.

COST PROHIBITIVE

Movie theaters, often housed in vast multistory buildings with multiple screens, are seen as particularly vulnerable to attack with their many required emergency exits, dark surroundings and scant staffing.

The metal detector issue has been raised in the past. Security specialists recall they were used at some cinema locations for a while after the Sept. 11 attacks on New York and Washington, D.C.

And they were installed in a Long Island, New York, movie house some 30 years ago after a stabbing death there, but they kept movie-goers away.

They are also cost prohibitive to run, said Howard Levinson, a security consultant who worked on the Aurora shooting.

"You need two to four people to run one side and on a busy Saturday night you would need eight people. And you can't use them on a Saturday night but not on a Wednesday afternoon," said Levinson, president of Massachusetts-based Expert Security Consulting.

Cheaper methods would include putting working alarms on all doors, better staff training and tighter emergency procedures to minimize potential casualties and summon help, he said.

"Theaters are struggling to stay alive and make a profit with what's been going on with cable TV and on demand. So they have to make it as nice and as safe as they can for people to come in and spend a few hours," Levinson said.

Movie admissions fell 6 percent to 1.26 billion in 2014, a 19-year low, said Paul Dergarabedian, analyst at film trackers Rentrak. But he said the latest attack is unlikely to deter cinema-goers this weekend.

Despite its association with the Aurora movie shootings, "The Dark Knight Rises" went on to make almost $450 million at the North American box-office and more than $1 billion worldwide.

Out of sight is ultimately out of mind, said Levinson. "A couple of days after (a shooting), if you were to ask people if they'd pay an extra $3 a ticket to be safe in a movie theater, a lot of people would probably say yes, who won't say yes in three months," he said.

(Additional reporting by Piya Sinha-Roy in Los Angeles and Joseph Ax in New York; Editing by Mary Milliken and Lisa Shumaker)