The Markets at Highlandtown, a few blocks away on Eastern Avenue, has seen a 40 percent drop in water and soft drink sales since the bottle tax jumped to 5 cents in July, said owner Avi Hershkovitz. A case of water at his store, for instance, costs $1.20 more than in nearby Baltimore County.

"The bottle tax is an unfair tax. It's only in the city," Hershkovitz said. "It should have been statewide. Being only in the city puts us at a competitive disadvantage with the county, which is only 1 mile away."

The bottle tax has had no effect on Eddie's Market in Charles Village, said owner Jerry Gordon, but he acknowledged that's because he's nowhere near the county border.

Eddie's customers make a trip to the store on Saint Paul Street near the Johns Hopkins University once a day or more, Gordon said. Even if they buy a beverage, a nickel more isn't enough to make them shop elsewhere, he said.

But Santoni's customers buy in larger quantities, and a 12-pack of soda becomes 60 cents more in the city than in nearby Baltimore County, Gordon said. That's enough for people to get in their car and shop in the county, he said.

When Santoni's shuts its doors, more than 80 of its workers will be laid off, the retailer said.

"Those jobs aren't coming back to the neighborhood," said Burt P. Flickinger III, managing director of Strategic Resource Group, a New York grocery consulting firm. And "there will be just as many jobs lost in the vendor community."

An earlier version of this story misstated the location of a nearby Shoppers. The Sun regrets the error.