Correction: A previous version of this article said Vice President Biden didn’t explain why he had chosen to attend the opening of the District’s first Costco store, but press pool reports quoted him during the visit as saying Congress needed to extend the Bush tax cuts for the middle class. The article also said Biden’s office could not be reached for comment. An e-mail request for comment was sent to the wrong office by mistake. This version has been updated.

Only in Washington would the vice president show up at a store opening, pushing a shopping cart and waving a membership card.

Joe Biden was among the throngs at Thursday’s opening of the District’s first Costco store, in the Fort Lincoln area of Ward 5.

Biden joined the ranks of other politicos who’ve made appearances at local businesses. President Obama dined at Ben’s Chili Bowl. Russian president Dmitry Medvedev dined at Ray’s Hell Burger. First lady Michelle Obama shopped at the Target in Alexandria, hidden behind sunglasses and a baseball cap.

Biden was less clandestine. He stopped for photos and hugs, filled his cart and happily grabbed free food samples.

The grand opening also was an opportunity for Biden to push Congress on extending Bush-era middle-class tax cuts. He also talked with shoppers and employees, calling them “hard-working folks who don’t need to see their taxes go up,” according to press pool reports.

And according to final campaign finance reports, Susan Brotman, the wife of Costco co-founder Jeff Brotman, bundled $508,646 in contributions for Obama’s campaign. Costco co-founder Jim Sinegal is a longtime Democratic donor and spoke at the Democratic National Convention.

But other shoppers who arrived en masse Thursday morning simply wanted to catch some bargains and see the big-box behomoth that finally opened after years of delays.

The store, flanked by New York and South Dakota avenues, is enormous — 154,000 square feet — and has created dozens of jobs. But that probably isn’t the main reason customers lined up on a cold Thursday morning before Costco had even unlocked its doors. Or why they entered the no-frills warehouse — which smells mostly of cardboard, wood and plastic — with wonderment in their eyes.

Costco stores aren’t pretty. They’re big and gray and drafty. People pay a membership fee just to get inside, where they spend more money than they really want to and indulge in way too many food samples.

According to Michael J. Silverstein, a senior partner of the Boston Consulting Group and an expert on retailing and consumer behavior, Costco’s rather intense fan base boils down to packaging “technical and functional benefits” — low prices for a wide variety of goods — with emotional appeal.

“Costco is a mystery shopping trip,” said Silverstein. “You go in with a list and always buy more. And Costco is a treasure hunt: You’re seeing things you’ve never seen before, tasting things you’ve never tasted before. . . . I say, if Americans are eating spanokopita, it’s because they got it at Costco.”

In many ways, it’s the Disneyland of warehouse shopping — with the promise of ad­ven­ture, whimsy and great deals just around the corner.

Now, that corner is much closer to home for D.C. residents.

Before this week, Washingtonians would have traveled to Pentagon City, or to Beltsville or Lanham in Maryland to reach the nearest Costco. For five years, the Fort Lincoln project stalled over a debate about protecting nearby wetlands.

The new location — the company’s 619th store worldwide — is the anchor of the Shops at Dakota Crossing, the retail arm of a planned community in Fort Lincoln. Costco is on a street so new that it might not show up on a Global Positioning System device. But from New York Avenue heading toward Maryland, you can’t miss it.

Sharon Davis, a Capitol Hill resident who came in to buy an armload of chocolate chips to bake cookies, dragged along a reluctant friend. Davis acknowledged that first-time visitors might find the warehouse to be “a bit much.”

Karen Watts, a Ward 5 resident who was perusing the electronics department with her husband and daughter, said she decided to come to Costco after seeing the waiting line featured on the morning news.

“I’m a piece of Costco woodwork,” said Karen Williams. “I go from store to store, wherever I am, just to see what they have, what’s new, what their exclusives are. My favorite store is in Wilmington, Delaware, because there’s no tax. But this — this is much closer to home.”

Rachel Weiner contributed to this report.