An investment manager from Manhattan who purchased an oceanfront home in East Hampton 15 years ago, Marc Healie, says that during the week the view from his balcony is one of the world’s most beautiful vistas. On weekends, he says, it’s a far different story.

In front of Mr. Healie’s multimillion-dollar home in the village of Amagansett, a large swath of prime beach real estate is being overwhelmed by trucks and SUVs that drivers are parking bumper-to-bumper along the water, often staking out spots for the entire weekend, and turning the beach into a makeshift parking lot. The popular tailgate beach scene is fueling a quarrel between New Yorkers with weekend homes and the trustees of the town who control the beaches over who has a right to have access to the waterfront.

“They’re blasting the radios in their cars while sitting on the beach,” Mr. Healie said. “I hear it 100 feet away when I’m trying to enjoy the peace and quiet on my own property.”

“It’s taken on an ‘us’ versus ‘them’ quality,” the East Hampton town historian, Stuart Vorpahl, said in an interview. “The beach is not a private resource, and they’re trying to turn it into one.”

The wrangle over beach access is widening the rift between year-round East Hampton residents, most of whom support open access to the beach, and city dwellers, who arrive in town only during the summer months and then put up a fight to restrict access to a scarce public resource.

On the weekends, Mr. Healie said, the trucks leave little room for sunbathers or beach walkers to enjoy the shore. “It’s an eyesore and it destroys all of the aesthetics,” Mr. Healie said of the many dozens of vehicles that park on the beach. Some homeowners also expressed concerns about safety for children and pets, as vehicles often exceed the 15 mile an hour beach speed limit.

The trustees of East Hampton, an elected body of nine created when the town was founded in 1686, has jurisdiction over the town’s public beaches up to the high tide line. To support a thriving fishing industry, the trustees for decades have allowed vehicles to drive to the water’s edge between Napeague Lane and the State Park. Beach vehicle permits are free for residents, and cost $200 a year for visitors.

These days, with few working fishermen using the beach, homeowners are questioning whether a law created to allow fishermen to make a living may be out-dated.

“They play music, take out jet skis, and use their trucks as cabanas all day at the beach,” another homeowner, who asked not to be named, said. “We end up sitting on the beach between trucks.”

With the popularity of four-wheel drive vehicles growing in recent years, some homeowners this summer are trying to change the law and reclaim their pristine beach from the tire marks and gasoline stains that pattern the sand in front of their properties.

“Our position is that, traditionally, vehicles have been on the beach in order to access fishing,” the clerk of the East Hampton Town Trustees, Francis Bock, said. “Unfortunately, the population has grown so much that now everyone’s fighting for their little square foot of beach.”

When asked if the law should be changed because of the SUVs and Jeeps taking over the beach, Mr. Bock said: “Then you have to ask, do those houses really belong where they are?” referring to the new multimillion-dollar developments that have risen from the dunes. “Local families like to go out there and get away from the traffic and spend the entire day with the car on the beach,” he said.

Many homeowners who purchased their summer homes during the winter months said the vehicles on the beach were never mentioned by sellers or real estate brokers, and came as an unpleasant surprise when the summer season kicked into gear.

While board members have been unwilling to limit access to the public beaches, residents are hoping to push their case this November, when all of the board members are up for re-election.

“Whenever the local government tries to impose restrictions on the use of the beach, the trustees come right out and say, ‘No, you can’t trample on our rights,'” a real estate broker and long time East Hampton resident, Htan Han, said. “I would not like to have my rights taken away from me, but I recognize how fragile the sand dunes are, and that it’s a fine line between use and abuse.”