When a music festival came to town, the manager of year-round boardwalk staple Ocean Art Gallery assumed he wouldn’t see extra business. You can’t take outside purchases into the festival, David Schroeder thought. So who is going to buy art?

He was wrong.

Oceans Calling, a multigenre music festival that takes place along the boardwalk in Ocean City, has exploded in popularity and spawned two related festivals, including one this weekend called Country Calling. Carrie Underwood, Luke Bryan and Luke Combs are headlining the three-day event.

Last weekend was the third annual Oceans Calling, featuring Noah Kahan, Green Day and Fall Out Boy. It sold out two of its three days. Oceans Calling and Country Calling have a daily capacity of 55,000 — in a resort town of about 7,000 full-time residents.

Schroeder recalled a customer in a previous year who picked out several dozen pieces before heading into the festival on a Friday and came back the next morning to buy those and another 12.

“When I was loading his car, I was like, ‘I should just close and go home,’” Schroeder joked.

The gallery sold seven times more than it would have on a regular Saturday in September, he said.

Oceans Calling, Country Calling and a springtime event called Boardwalk Rock are produced by Austin, Texas-based events company C3 Presents. Owned by Live Nation Entertainment, C3 has spearheaded events such as Lollapalooza and Austin City Limits Music Festival.

These and other festivals are helping Ocean City — by this time of the year usually retreating into its sleepy months — extend peak season. That has boosted local businesses, hotels and residents who rent their places to festival-goers.

Sunfest, a free, annual four-day fall festival, is this month. Rising Tides Festival, a throwback music festival celebrating the 1970s-2000s, will debut next month, and a gala celebrating Ocean City’s 150th year is set for mid-December.

Together, Oceans Calling and Country Calling generated $376.3 million for the Ocean City economy last year, according to an economic impact study conducted by AngelouEconomics and provided by Ocean City.

“Beyond the numbers, these festivals not only bring international talent to our beach but also welcome thousands of new and returning visitors on back-to-back weekends,” said Jessica Waters, marketing and communications director for Ocean City.

Tim Sweetwood, director of the C3 festivals, said Ocean City is “very supportive and understands the economic impact that these festivals can bring to the town, let alone the area, let alone the state.”

But there are costs to Ocean City and its businesses, too.

Staffing for large crowds during offseason can be an issue with the J-1 visa students and local college students gone, business owners said. And some businesses too far outside the festival perimeters don’t see much economic impact, while some businesses too close see a drop in regulars that isn’t offset by the music crowd. The festival also means an early closing time for bars and restaurants inside the security gate.

Oceans Calling and another Maryland festival, All Things Go, which takes place the same weekend in Columbia, are outliers in their recent growth. Overall, music festivals worldwide are struggling.

Much of any festival’s revenue comes from sponsorships, food and beverages merchandise — and sometimes even government grants.

The C3 festivals in Ocean City are receiving $1.65 million from a state tourism fund from 2023 to next year, according to the Maryland Sports Commission, which administers the money.

Amy Thompson, president of the Ocean City Chamber of Commerce, said it took lots of conversations among C3, the town and businesses to get everyone on board.

“You can’t imagine how big a deal this is to business owners who are used to doing things the way they do them,” she said. “It is a disruption from traditional fall activity at the beach.”

She said the town and festival “try meeting everyone’s needs as best we can.”

The choke point of Oceans Calling’s North First Street gate creates a sort of haves and have-nots for retailers. Those just outside the perimeter must count on attendees being willing to take purchases back to their cars or hotels because the festival restricts what they can bring in.

Sean Lackner, co-owner of Dream Weaver, a boardwalk shop that sells jewelry, tapestries and clothing, has experienced both sides of the gate.

Last year, the shop was outside. This year, because organizers extended the festival footprint, it was in.

The rainy Saturday drew customers, Lackner said, though he expected bigger crowds.

“Talking to some of our neighbors just outside the gate, telling them it was hit-and-miss for us, they said, ‘Well, if it’s slow for you, it’s dead for us,’” Lackner said.

Malibu’s Surf Shop, a family-owned business since 1986, is a few blocks outside the gate.

While the shop might not see the same benefits as those inside the festival footprint or businesses such as hotels, foot traffic does pick up, owner Lee Gerachis said.

And the festival brings in people — including a customer from Norway — who might not otherwise visit Ocean City, he said.

The family members who work at Malibu’s split work hours so that everyone had a chance to attend the festival.

The Purple Moose Saloon is within the festival footprint — which it sees it as a positive and a negative.

“Overall, we do great volume and great sales,” said Bobby Taylor, general manager. “It’s great for the town.”

But he noted that bars and restaurants inside the gate don’t love the 11 p.m. curfew related to the festival. They’d usually be open until 2 a.m.

Festival setup means those same places also close early Thursday. And the public can’t access businesses when the perimeter is established.

“I feel like every year they [C3] push a little more when it comes to me trying to operate my business,” Taylor said.

Yet Taylor said the C3 festivals are well managed and well policed.

Oceans Calling is “probably one of the best l’ve seen in Ocean City as far as that goes,” he said. “I’m happy overall with it.”

Banner reporter Wesley Case contributed to this article.