In staging nationwide protests at Wal-Mart stores on Black Friday, employees and labor unions are turning back the clock – trying to influence America’s largest retailer in ways that were the norm before the union movement started in the 1930s.

The disgruntled employees group organizing Friday’s walkouts, called Organization United for Respect at Walmart (OUR Walmart), complains that Wal-Mart pays low wages and sets unfair labor conditions. But since Wal-Mart employees are not organized into a union, they can’t strike to air their grievances.

Instead, the Black Friday protests are only the latest – and most ambitious – of a series of attempts by OUR Walmart and others to publicly shame the company into listening to grievances.