McDonald's did not return multiple calls for comment. A company spokeswoman, in a statement emailed to CNBC, said Low Pay Is Not OK's video about the website took the advice out of context and characterized the campaign as "an attempt by an outside organization to undermine a well-intended employee assistance resource website."
Although the spokeswoman said McDonald's and Nurtur Health, which created the site, would "review the content and make any necessary adjustments," she defended the site. "The vast majority of the resources and information on the site are based on credible outside experts and well-published advice," she said.
An executive at Nurtur Health referred queries to McDonald's public relations department.
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Ruth Milkman, a professor of sociology at the City University of New York, said the advice is "probably well-intentioned but shows deep ignorance of what it means to survive on a low wage job. Between the low wages and the short hours, it's tough out there."
Felicia Cochran, a McDonald's drive-thru worker who earns less than $8 an hour, criticized the advice about returning holiday purchases in an online chat. "If I've already bought my kids their gifts, I just couldn't do it to them to return their things. We're already poor as it is and we have to do without so much," she said.
Cochran said she hadn't used the McResource Line, but that she's "lucky" to get two days a week on the schedule and she's on food stamps, "cause $7.78/hr doesn't afford much of anything for making a living."
In an earlier campaign, Low Pay Is Not OK reported that the advice given to a McDonald's worker who contacted the McResource Line by phone was to apply for food stamps.
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McDonald's isn't the only company facing criticism for its wages. Wal-Mart Stores came under fire after an article Monday in the Cleveland Plain-Dealer showed photos of the employee area of an Ohio store housing a food donation bin — intended for workers to supply food to other workers.
The flap over McDonald's advice and the Wal-Mart employee food donations highlight a broader challenge pertaining to the burgeoning number of low-wage jobs in the American economy, said Anthony Carnevale, director of the Center on Education and the Workforce at Georgetown University.
"What we have here is one more situation where workers are fairly powerless," he said. "It raises issues about living wage and minimum wage."
Shrinking union clout and an increasingly bifurcated economy rife with low-wage service jobs give Americans without a college degree less of a chance than generations before them of earning enough for a middle-class lifestyle. "It raises a fundamental question about upward mobility," Carnevale said.
—By Martha C. White, NBC News contributor