The demonstrators said they were also protesting retaliation by Walmart. Last January, the National Labor Relations Board accused the company of illegal activities in 14 states, in particular in the disciplining of about 70 workers — and firing more than a dozen of them — for participating in previous protests. Those accusations are pending, and Walmart said the labor board had not made any rulings that the company acted unlawfully against Our Walmart members.

Linda Haluska, a nighttime stocker in Glenwood, Ill., was among those arrested for obstructing traffic outside a Chicago Walmart. “I do believe not just this protest, but many protests I made in the past, they all make Walmart pay attention to us,” said Ms. Haluska, who earns $12.65 after nine years at Walmart. “Although they don’t give us credit, they listen to us.”

The group insists that Walmart has responded to its protests by announcing it would make more workers full time and start paying all its employees more than the minimum wage.

Kim Bobo, executive directive of Interfaith Worker Justice, an advocacy group for low-wage workers, demonstrated with about 40 people, including two priests, at two Walmarts in Alexandria, Va. She said many members of the clergy had urged their parishioners to join in.

“We talk with everybody in congregations — plan your Thursday with your family and your Friday morning at your local Walmart,” she said. “That’s what a lot of social activists are beginning to do. That’s becoming part of our tradition.”