Police tape blocks off a movie theater in Aurora, Colo., where a gunman attacked movie goers on July 20, 2012. (Credit: Thomas Cooper/Getty Images)

The massacre at the Century 16 Movie Theaters in Aurora, Colo., early this morning has business owners and patrons asking what more can be done to improve security at public gathering places.

"I don't know if you could ever really avoid this," said Geoffrey Kohl, conference director for secured cities, a national conference on urban cities. "If you could throw all the security measures at it, you could likely minimize it." But there's only so much that can be done.

"If you went through those drastic measures -pat downs and metal detectors - it would not be an enjoyable experience and you'd also be putting a cost on theaters that they may not have the profit to bear," he added.

Cinemark, which owns the theater in Colorado, has 459 theaters in the United States and Latin America, according to its corporate page. The company is the third-largest chain in the U.S. with 298 theaters and 3,895 screens in 39 states.

Cinemark did not immediately return our request for comment on security measures. In a statement, the company said: "Cinemark is deeply saddened about this tragic incident. Our thoughts and prayers are with the victims, their families and loved ones, our employees, and the Aurora community. We are grateful for the quick and professional reaction of all local law enforcement and emergency responders. Cinemark is working closely with the Aurora Police Department and local law enforcement as more facts develop."

Founded in 1984, the Plano, Texas-based chain operates under Century Theatres, CineArts, and Tinseltown.

Initial reports were that the Colorado gunman bought a ticket, went in and sat down with the crowd. About 30 minutes in, he exited the cinema to the parking lot though an emergency exit then returned through the same door heavily-armed and opened fire.

A spokesperson for National Association of Theatre Owners said, ""We are grateful for the quick and effective response by police and emergency personnel. Guest safety is, and will continue to be a priority for theater owners. NATO members are working closely with local law enforcement agencies and reviewing security procedures."

Theaters in New York City and Washington, D.C. reported they are beefing up security for movies showings in the wake of the shootings. Police Commissioner Ray Kelly said in a statement that the decision was "a precaution against copycats and to raise the comfort levels among movie patrons."

Carlo Petrick, a spokesman for Marcus Theatres, which has 600 U.S. screens, told Time in a statement: "These senseless, random acts of violence, by disturbed individuals, can happen anywhere, but have never occurred in a U.S. movie theater in its 110-year history. Safety and security of our guests and associates is always a priority concern. We will take appropriate measures to have our security precautions in place today and every day. All showings of 'Dark Knight' and all other motion pictures at all Marcus Theaters will go on as scheduled."

The Colorado theater is the just latest business impacted by violence on patrons.

About 11 days ago, a gunman wounded five people after opening fire in the parking lot of Oakland's Jack London Square at the Regal Cinemas in California. Since the shooting, its business as usual at the multiplex, with "The Dark Knight Rises" expected to play at 11:40 a.m., according to Fandango.

In Seattle, a gunman opened fired at Cafe Racer Expresso in Seattle, killing five people two months ago. While the doors of the Cafe closed for seven weeks, an unnamed worker told ABC News today, "our community rebuilt the cafe." While the doors were shuttered, numerous fundraising efforts were held to to help the victims of the shooting, including Cafe Racer Lover.

Kohl says theater and concert venue owners need to step up their vigilance. "I think you have to have your staff start to identify people coming in. Maybe when you're trying to identify people bringing in extra food, you're scanning your customers as they come in to keep them from bringing that [weapons] in. Is there a bulk on this person that might be concealing? You have to start with your employees. Bringing them into a security awareness," said Kohl.

Staff must be trained to react in case there's a threat. "Questions you should ask if there is danger: Do you evacuate? Do you shelter in place. Do you turn the lights on? Do you dim the lights? What do you do with your staff? Your staff are trained in collecting tickets, making popcorn but they're not trained as security. How do you train them in assisting guests? Bring in a professional security consultant and start to consider those," Kohl advised.

But, ultimately violent acts by people intent on doing as much damage as they can and with easy access to firearms is unavoidable.

"This is a rare occurrence and I'd like to think this would stay a rare occurrence," said Kohl.