ANAHEIM (CBSLA.com) — As the iconic restaurant chain marked the opening of its 300th location on Wednesday, In-N-Out Burger fans pulled an all-nighter, and owner Lynsi Snyder welcomed Double-Double fans to the store on State College Boulevard near Ball Road in Anaheim.

Snyder, the granddaughter of In-N-Out founders Harry and Esther Snyder, was on hand as the store was dedicated to her grandmother on what would have been her 95th birthday. Lynsi Snyder, who worked behind the counter at In-N-Out as a teen, inherited the company when her grandmother died in 2006.

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“What reminds me of my grandma is just seeing everyone smiling and the team atmosphere because it’s so important to us to look out for one another, have each others’ back,” Lynsi Snyder told CBS2’s Michelle Gile just prior to Wednesday morning’s opening.

Snyder, 32, who is now one of the wealthiest women in America, became president of the restaurant chain in 2010.

In-N-Out started in 1948, and other than branching out from Southern California to add locations elsewhere in the state as well as in Arizona, Nevada, Utah and Texas, not much has changed.

“You know, we’re not like a lot of other people just trying to bring in new things and all that, because what we have does work, so why change it?” Snyder asked.

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That suits customers like Kurt Zimmerman just fine. He arrived at 2 a.m. Wednesday to be the first customer in line.

“I’ve never been to an opening. The closest thing is like a midnight showing of a movie,” Zimmerman said while waiting in line.

His three-patty burger with fried mustard was order No. 1.

“I am dying to try it,” Zimmerman said. “The first burger at a new place, it’s got to be the best.”

Snyder let Gile in on one of In-N-Out’s secrets. Often, when a location opens, a new hire will be encouraged to water the plants.

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“As you might see, the plants are not real, so it’s kind of a little prank,” she said with a smile.