Gold chokers and bracelets sit atop a white table at AUrate's jewelry store on a balmy June day in Southampton, N.Y., a high society playground at the eastern tip of Long Island. Shoppers peer through store windows as they stroll by, clad in their typically relaxed Hamptons uniforms—preppy nautical summer dresses, oversize sunglasses, lots of stripes.

The AUrate New York shop will only be open for a few months, a temporary pop-up seeking to test the market. Laid out next to the jewelry lies a selection of handmade belts from a label called Upton. A co-founder is there for the weekend, hawking his leather bands.

It's a pop-up shop inside a pop-up shop.

The Hamptons is a breeding ground of chic pop-up shops during summertime, as brands converge on its various towns to sell their wares. Most are fashion, jewelry, and beauty labels that open around Memorial Day weekend or later. This summer, designer Jenni Kayne takes her minimalist California style across the country to open a Southampton shop. Gurney's Fashion Collective is a rotation of shops on a roof deck in a Montauk hotel. Italian label Aquazzura brings its trendy sandals and espadrilles to the East Hampton main drag. Jewelry maker Miansai is filling up up a shiny Airstream trailer with its baubles and taking it to the beach.

Each June, the area morphs into a sun-soaked wonderland for beachgoers, weekend partiers, and socialites who savor the country club scene. It's a tiny corner of the country that's created an aura of refinement, the epitome of East Coast prep alongside Martha's Vineyard and Nantucket. Celebrity sightings are frequent, and many own homes there, from Martha Stewart to Sean Combs. The Kardashians based one of their reality shows in the Hamptons, following Kourtney and Khloé as they opened a pop-up for their Dash fashion boutique.

How It Works

Months prior to the summer rush, during the previous fall, reps from national brands hoping to test the Hamptons waters meet with real estate agencies seeking store space in the area. There's been a long fight to get national chains to stay permanently, so that there are fewer vacancies during the quiet winters and less annual turnover. But the stark seasonality of the region still opens up lots of room–16 stores were available in East Hampton this year during the planning months. Southampton had a similar number.

But by the end of spring, every available location on each main shopping street is inevitably filled, either by permanent stores or temporary ones, said Hal Zwick, director of commercial real estate for Town & Country, a firm with offices throughout the area. Commercial rentals shifted to shorter leases during the recession, and some retailers still want no more than a few months, or even weeks, in a space. Although Zwick largely deals with well-known brands as clients, lately he's noticed more smaller labels moving in. This year, with so much space available, many were able to score spots.

AUrate New York co-founder Sophie Kahn put her shop out in the Hamptons because it's a low-risk way expose her label to affluent New Yorkers, a precious trend-aware class that values fine jewelry. Indeed, much of the annual Hamptons exodus comes from New York City, urban dwellers looking to get away from the bustle or the wealthy crowd headed to their summer mansions. The region's various hamlets have been a gathering point for the city's elite for more than a century.

"It has a certain, I would say, elevated feel to it," said Kahn. "It's luxury."

Shops like AUrate hope to find new customers who they can retain for the long haul. If passersby step inside and don't buy anything, at least they saw what the label has to offer. This, for a small company, is invaluable. Even if Kahn doesn't decide to come back next year, or stay permanently, she's assured some benefit.

That's a big reason pop-ups of all types are getting more popular. Such cities as New York and London host hundreds of pop-ups each year, attracting shoppers with fleeting exclusivity. A whole industry has grown around pop-up dining, where foodies can try new, one-of-a-kind culinary experiences in places ranging from the Australian outback to a farmhouse in the British countryside.

Private Events

Then there are the parties. Houses, art galleries, country clubs, and stores host celeb-packed events throughout the warmer months. It's a social scene brands can't resist. Take Armarium, a fashion rental company that will run a pop-up concierge service at a Sag Harbor hotel this summer, with stylists to help socialites figure out the right look. Armarium's name is frequently seen in social hotbeds such as New York, Los Angeles, and South Florida, seeking out shoppers attending posh events and dinner parties. For that purpose, the Hamptons aligns perfectly.

"We're servicing a girl who's looking for a statement piece," said Trisha Gregory, co-founder of Armarium. "She's not basic."

But the demographic has lured plenty of full-time tenants for the pop-ups to compete with, too. Most are established labels, not plucky startups. J. Crew, Ralph Lauren, and Club Monaco each have outposts on main shopping strips, for instance. A glimmering new Tesla showroom, now a permanent fixture in East Hampton after a successful pop-up trial last summer, was this year's biggest new opening.

Plenty of stores never come back. Joe Fresh didn't open a full-time store after operating pop-ups in multiple Hamptons towns. Neither did Rebecca Minkoff. Designer labels Milly, Isaac Mizrahi, and Tamara Mellon each opened temporarily alongside high-end boutiques but didn't stay. Dash, the Kardashian store, lasted only one season.

That doesn't necessarily mean they failed. Touting a Hamptons shop gives brands an air of exclusivity and a connection with the moneyed society. Plus, the short lives of pop-ups drum up lots of hype and exposure. For big brands, it can be worth the bet, even if the store doesn't end up profitable. For smaller labels that count every penny, there's much more hand-wringing. Even for AUrate, which has held pop-up locations before, running a shop for a full season (and paying gobs in rent) can be daunting.

"This is our riskiest one so far," said Kahn. "So yes, it's scary."

A Launching Pad

The payoff can be worth a few nerve-wracking months. Some new stores, birthed as seasonal Hamptons shops, have been able to score long-term success. Athletic-wear shop Bandier, which started as a single summer store that opened in Southampton in 2014, has expanded to six full-time locations, including a flagship store on New York's Fifth Avenue. Bandier's Hamptons location looks different from its other shops, which are emporiums of stretchy pants and performance tops meant for the spin studio or barre class. It's filled with items it doesn't sell elsewhere—sunglasses, swimsuits, cosmetics, clothes for golf and tennis. The Hamptons shop continues to shut down during the off months, and hosts pop-ups for other labels, such as a trunk show for Reebok.

"Originally, I thought I'd open in New York," said founder Jennifer Bandier. "But the rents were so high."