Visits by loyal Stop & Shop customers decline 75 percent during strike

Some shelves at a Stop & Shop in Malden were empty on Friday. Nathan Klima for The Boston Globe

In the first few days of the Stop & Shop strike, visits to the grocery chain by regular customers dropped by a whopping 75 percent compared with the previous weekend, according to an analysis of mobile device data by Skyhook, a location technology and intelligence company based in Boston.

Many loyal customers — those who typically visit Stop & Shop once a week — did not go grocery shopping at all that first weekend, the analysis found, with visits to all area grocery stores decreasing by almost half, likely a result of shoppers holding out in case the strike ended quickly.

The strike, which involves 31,000 workers at 240 stores in Massachusetts, Connecticut, and Rhode Island, began abruptly last Thursday afternoon when workers got the call from the United Food & Commercial Workers union to walk off the job. The workers — three-quarters of whom are part time, according to the union — have been picketing ever since, protesting proposed increases in health care costs, reductions in pension contributions for many nonvested part-time workers and new hires, and changes to Sunday and holiday overtime pay for current and new part-time employees.

Friday night, a Stop & Shop spokeswoman said the company and the union were “continuing negotiations into the evening.’’

A shopper walked out of a Market Basket in Reading. The rival grocery chain has seen a 115 percent increase in business since the Stop & Shop strike began. Nathan Klima for The Boston Globe

The strike has boosted business considerably at Stop & Shop’s competitors around the region, according to Skyhook’s analysis, particularly at Hannaford, which had four times the number of visits from loyal Stop & Shop customers April 12-14 compared to the weekend before. Market Basket got a 115 percent hike, while Trader Joe’s saw a 75 percent rise and Shaw’s and Star Market had a combined 50 percent increase.

And once shoppers defect to a different store, analysts say, as few as 40 percent may return after a strike is over.

“The strong support for the strikers and people’s aversion to crossing over [picket lines] and going to a Stop & Shop store is so clear,” said David Bairstow, head of product for Skyhook, noting that the trend continued into this week.

The significant increase at Hannaford, which is owned by Stop & Shop’s parent company Ahold Delhaize, is likely due to the fact that there are relatively few Hannafords in the region, magnifying the effect of more shoppers going there.

The data confirm anecdotal reports from around New England that the strike is having a major impact on the Stop & Shop chain. Dozens of stores are closed, according to union estimates. In those that remain open, hours are limited to 8 a.m. to 8 p.m.. Deli, seafood, bakery, and customer service counters are shut down, meat selection is limited, and gas stations are closed. Deliveries to some stores around the region have also been delayed, as union drivers refuse to cross picket lines and striking workers block the paths of trucks. Many shelves, and parking lots, are largely empty.

Negotiations continue as the strike stretches into its 10th day.

For its Stop & Shop analysis, Skyhook identified 840 customers in the strike-affected region who visit the grocery chain at least once a week, using location data from the 100 million mobile devices it has access to through software running in apps on those phones. This data, authorized by users, leaves “bread crumb trails” showing where people have been, Bairstow said.

Skyhook also has a database of venue locations, including grocery stores, and can track how often people visit.

An empty Stop & Shop parking lot in Malden on April 19. Nathan Klima for The Boston Globe

Steve Tarbell is among those who are shopping elsewhere — and he has no plans to go back once the strike is over. Tarbell, 60, who lives in Walpole, used to shop at the Norwood Stop & Shop almost every day, he said, mostly because he’s a creature of habit and knows where everything is. Since the strike, however, he has been going to Shaw’s in Sharon, which is only a few miles farther down the road, and he’s happy with what he’s found: a clean, well-stocked store with helpful employees and a better selection of meat and produce.

Tarbell, who worked in retail management for 30 years, isn’t staying away from Stop & Shop to support the union, as many people are. He just doesn’t think the store will have everything he needs. And he’s not a big fan of the staff.

“My impression is that they’re working harder right now in the picket line than they ever do in the store,” he said. “I’m not going back.”

It only takes 10 days for shoppers to form new habits, said Burt Flickinger, a grocery industry analyst with New York-based Strategic Resource Group, who estimated that the number of loyal Stop & Shop shoppers staying away could be as high as 80 or 90 percent.

This week, leading up to Easter and Passover, is the biggest of the year so far for grocery stores, he noted, and Stop & Shop — the only major chain in New England with a largely unionized workforce — could be losing $2 million a day. This has been a boon for other stores, Flickinger said.

“There’s such a high percentage of shoppers shifting over, and this is such a profitable week,” he said. “Competitors are proverbially dancing on the tables.”