Wal-Mart store in Secaucus, New Jersey - Jin Lee-Bloomberg via Getty Images
So maybe folks are still down on Wal-Mart's (WMTscant pay and benefits, its stance on working conditions in Bangladesh and its value compared with Costco's (COST). But even the megastore's foes say the pressure on Wal-Mart is doing wonders for it.

Union-backed Our Wal-Mart spent Friday protesting the company's annual meeting after a year of battling the chain on labor laws and being sued by the superstore for disrupting business. Still, the United Food and Commercial Workers Union tells The Huffington Post that the pressure from labor groups has led to visible changes within the company.

While the union rattles off anecdotal victories -- wages raised, firings undone -- it points to the strikes held during Black Friday last year as its biggest triumph. With workers frustrated by the company's decision to extend its Black Friday sales into the Thanksgiving holiday, Our Wal-Mart and Wal-Mart employees held a series of strikes that not only rattled Wal-Mart but inspired lawsuits against Our Wal-Mart for its "disruptive tactics."

It also led the company to adopt a pilot program created by workers who petitioned management at their Maryland store to let workers request vacant shifts in other sections of their stores. Wal-Mart may have forced itself into that position by shrinking its staff from more than 338 workers per store to 281 since 2007, according to a report from The New York Times. That led to bare shelves waiting to be restocked, snaking checkout lines in desperate need of cashiers, and hordes of angry customers taking their business elsewhere.

"Every time something happens to Wal-Mart, that's a win for Costco. That's a win for Kroger (KR)," Burt Flickinger, the managing director of the consulting company Strategic Resource Group, told The Huffington Post. That leaves Wal-Mart little choice but to work with its employees, who also have few other options.

Nationwide, 4.3 million Americans work as retail salespeople, giving them America's most common job, just ahead of the 3.3 million cashiers who work beside them, and earning them an average of $25,000 a year -- or well less than the nearly $46,000 annual mean wage.

Wal-Mart employs a whopping 1.5 million members of that labor pool. With Our Wal-Mart and others increasingly making Wal-Mart workers aware of their rights and organizing them to fight for better wages and hours, Wal-Mart suddenly finds itself in the same position as some of its competitors.

If Costco can offer low prices while giving the Teamsters a three-year contract, maybe an evolving Wal-Mart can make peace with its disgruntled employees before they decide to unionize.

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