"The company has built a strong customer base over decades, in part because consumers trust that it treats its workers fairly," the treasurers wrote. "A labor dispute of this magnitude risks eroding that trust, driving loyal customers to competitors and causing lasting damage to Stop & Shop's brand."

Company leaders say they're holding fast to the midnight Friday deadline for the union to agree to its contract. Meanwhile, 30,000 Stop & Shop store employees vow to 'stand arm and arm and in lock step' with warehouse Teamsters in the event of a strike.