If you didn’t know better, you would’ve thought it was a U2 concert. The parking lot was filled with people who had camped overnight to be first in line.

With daylight, the line began to lengthen, eventually stretching more than two miles, while police directed traffic. The wait to get inside was three hours. 

What was causing all the commotion? An In-N-Out Burger, opening for the first time in Frisco, Texas, in May 2011.

One customer reportedly shed happy tears after tasting her first Double-Double, while others came to the grand opening proudly wearing In-N-Out T-shirts and caps they’d bought online.

Some say this California-based burger chain has a cult following, and that the fans are fanatics.

Perhaps, but the family-run eatery clearly found a winning formula back in 1948, when it first opened — and it isn’t about to change now.

Regular customers such as Bill Brooks wouldn’t have it any other way. The owner of My Pool Co. in Redlands, Calif., takes his two young sons to In-N-Out at least twice a month. He says he prefers this burger place over others because of the food quality and the way the business is run.

Like most folks, Brooks likes In-N-Out’s simple menu featuring three kinds of hamburgers, three types of milkshakes, and a small selection of beverages. That’s all they offer. Well, except for the “secret menu,” which developed over the years as customers asked for — and got — special items, such as the Animal Style Burger (a humongous burger with all the fixings) and the Neapolitan Shake. None of the items actually appear on the menu; insiders just know what to ask for.

As fun as a secret menu is, there are even more fundamental reasons people frequent this restaurant.

“They get things right and they work fast,” Brooks says. “Your order is never screwed up, whereas if you go to other drive-throughs, you’d better check the bag before you leave.” He calls In-N-Out a “well-oiled machine.”

It’s also known for its employee-friendly policies. Founders Harry Snyder and his wife, Esther, reportedly were committed to treating customers and staff well.

The Snyder family has always paid its “associates” higher wages (minimum $10 hourly, to start) than competitors, along with full medical benefits, a 401(k) plan and paid vacation. Managers start at $100,000 yearly, with bonuses tied to store performance, according to sources close to the company.

Quality was so important to Snyder that he went to meat companies and watched the butchers to ensure he got what he wanted. In the ’60s, when the food industry turned to frozen beef patties and French fries, Snyder began hiring butchers to maintain the quality of his beef. That practice continues today at the firm’s regional distribution centers, located near the 258 restaurants in California, Arizona, Nevada, Texas and Utah.

In-N-Out Burger’s fierce dedication to “quality, freshness and service” has led to phenomenal word-of-mouth and new customers daily.

Such a success story can be inspirational to other businesspeople. Brooks, whose route averages 130 pools, says he, too, gets business by word-of-mouth. But other factors also come into play. “There are a lot of facets to owning your own business,” he explains. “You must be a people person, communicate well with customers, be a salesman and do everything, not just what you want to do, such as technical work. And you must have organizational skills.”

He adds, “I’m not big on being told what to do. I stay in the [trade] for the money and the freedom of owning my own business.”

Harry Snyder couldn’t have said it better.