It has also driven off customers and left the partners - both card-carrying members of the musicians union - more than a little confused about their personal position on organized labor.
"I always thought unions were good and played an important role in our country's history," Lokoff said. "But I 100 percent believe I did not do anything wrong."
His partner was more sanguine: "Maybe at this point, I'm a little antiunion."
After months of silence, the two have decided to strike back, with humor.
They recently printed T-shirts that matched the protest banner "Shame on MilkBoy," and sold them to loyal customers with proceeds going to charity.
They sold out quickly, leading to a second MilkBoy T-shirt that reads, "Menace to Ardmore."
"We were trying to make light of the situation," said Lokoff, 45, who lives in Philadelphia with his wife and three children. "If we didn't laugh, we'd be crying."
The union demonstrators rarely say anything, much like their boss, carpenters union chief Edward Coryell Sr., who did not return phone calls for comment.
Instead, they've spelled out their side of the argument in leaflets they hand out to Ardmore customers: that the owner of MilkBoy's pending Philadelphia site, U3 Ventures, is damaging the local economy by hiring two subcontractors that use lower-wage nonunion labor.
Lokoff and Joyner, both commercial musicians, are members of the American Federation of Musicians. They still get union work writing jingles for products such as Huggies. "We try to get as many as we can, because they're good money," Joyner, 40, said of the union gigs.
Joyner is originally from South Carolina; Lokoff grew up in Wynnewood. Both played in bands and did the New York scene before fate united them in Philadelphia.
Joyner moved here to open a recording studio upstairs from Zapf's Music in North Philadelphia, and Lokoff – who was writing music and doing some acting – needed a studio.
The North Philly space had been named MilkBoy after a picture Joyner had seen on a drum set, and Lokoff said "Milkboy" had also been his childhood nickname because he was allergic to milk. "It was kismet," he said.
They eventually ran the studio together, then found a site in Ardmore in 2001 when their Philadelphia lease ran out. The coffee shop came about in 2005, when they decided there was a need for an all-ages music venue in the area.
"Kids are connected to music, and there are 20 high schools and colleges in a five-mile radius," Lokoff said. "We thought, we'll create something that didn't exist, someplace for kids to go."
The idea was so successful that a year later, the Bryn Mawr Film Institute asked them to run the coffee shop next to its theater.
But moving back into Philadelphia has proved a lot more complicated. Lokoff said they were approached by U3 about opening a cafe on a block across from Thomas Jefferson University Hospital that's a rare cultural dead zone in Center City.
With a city development loan, U3 hired contractors for a major renovation. Some were unionized, but two - AM Painting and Mapo Builders - were not, triggering protests at the construction site and in Ardmore. Lokoff said he was told that using only union workers could have increased labor costs threefold.
"I heard we might encounter something like this because we knew we couldn't afford to hire all union workers," he said.
Similar protests over nonunion labor have taken place at other businesses, including the three restaurants owned by Marc Vetri.
The partners said they talked to Sue Schlisman, owner of Sam's Grill in Wynnewood and two Philadelphia restaurants, Devil's Alley Bar & Grill and Smokin' Betty's.
Schlisman told them her unwillingness to use union workers led to lengthy protests at her two city spots, not just by the carpenters but by unionized electricians she accused of gluing her locks every morning, costing $100 each time.
"I can't make them eat in my restaurants, so they have no right to make me hire them," said Schlisman, who believes all the attention has helped business.
The owners of MilkBoy said sales were off by 5 percent or more just as things were starting to pick up at the end of a long economic downturn. "Customers have been up at the counter and ordered coffee and they'll ask, 'What's the picketing about?' and they've asked for their money back," Lokoff said.
"With everybody hurting, including the carpenters, trying to attack a small business, to inflict additional pain, is wrong," Joyner said. "It's mean-spirited." He said he was a small-business owner who lives in a modest twin in Ardmore "doing anything I can to survive."
Lokoff said he hoped a rising economic tide can lift all boats.
"I believe that if we open up at 11th and Chestnut and we're successful and we create some energy on that corner . . . it will suddenly become more attractive to bigger businesses that can afford to pay union wages."
Contact staff writer Kathy Boccella at 610-313-8123 or email@example.com.