Panini and Company Cafe normally sells sandwiches to tourists in Lower Manhattan and the residents nearby, but in recent days its owner, Stacey Tzortzatos, has also become something of a restroom monitor. Protesters from Occupy Wall Street, who are encamped in a nearby park, have been tromping in by the scores, and not because they are hungry.

Ms. Tzortzatos’s tolerance for the newcomers finally vanished when the sink was broken and fell to the floor. She installed a $200 lock on the bathroom to thwart nonpaying customers, angering the protesters.

“I’m looked at as the enemy of the people,” she said.

The anticorporate participants in Occupy Wall Street, which began three weeks ago, say they have no intention of leaving soon. The protest has been building in size, with sister demonstrations erupting in other cities, and politicians, labor leaders and celebrities adding their support. But for many neighborhood businesses, the protest’s end cannot come soon enough. In interviews, business owners said they were especially annoyed that the organizers of the grass-roots movement neglected to include portable toilets in their plan to bring down Wall Street.

Residents, too, say they are losing patience.

Mothers have grown weary of navigating strollers through the maze of barricades that have sprouted along the streets. Toddlers have been roused from sleep just after bedtime by chanting and pounding drums.