In every one of Wal-Mart's thousands of stores they begin the day with a company cheer. It's supposed to inspire employees and remind them that the customer comes first.
We spoke with employees who say they like working for the retail chain, but others call the workers victims of "exploitation."
Critics say Wal-Mart is responsible for wrecking communities, discriminating against women, failing to provide good health benefits and underpaying its workers.
Robert Greenwald's new documentary, "Wal-Mart: The High Cost of Low Price," depicts the retail giant as a greedy beast grabbing everything in its path.
Now, a big union-led campaign intends to force Wal-Mart to stop being "greedy." Paul Blank was hired by the Food and Commercial Workers Union to convince people not to shop at Wal-Mart until the company pays workers more.
"For a one-penny increase, they could provide their workers with $2 more in wages and benefits," Blank told "20/20." "The average associate at Wal-Mart makes $8.23 an hour … that's not a job that can support a family."
In response, Wal-Mart says the average wage is about $1 an hour more than that, but it's still not a lot.
"They have taken the values, the morals, the ethics, fairness that are the fabric of our society and put them aside and … put their profits before their people," said Blank.
The children of Wal-Mart's founder, in contrast to its workers, are billionaires. Does that make them greedy?
They wouldn't talk to us about that. But three years ago, another billionaire, Ted Turner, did.
The media mogul called greed "ambition."
"America is about competition and rising above that competition. That's at the basis of what makes our … economy and our society tick," said Turner.
But in America capitalists are often vilified, as if one person's success means another's loss.
"That's really a child's view of -- of how the world works," said philosopher David Kelley, of The Objectivist Institute.
"It's like we're all children sitting around the dinner table and a pie comes," said Kelley. "If I get a bigger piece, you get a smaller piece. But in reality, there's no mom there putting a pie down on the table. We're producers, we create wealth."
Wal-Mart certainly created wealth. The chain started with just one discount store. Its owner, Sam Walton, invented new ways to streamline the supply chain and speed delivery to stores. He pushed suppliers to sell for less so he could sell for less.
That strategy was so popular, Wal-Mart now has more than 6,000 stores and sells more goods than any other chain.
As a result, Walton's heirs got rich. But does their having billions mean the rest of us have less? No.
"This is the fallacy that there is some pool of wealth there that's fixed, and if I take more you get less. That's not true," said Kelly. "Wealth is constantly being created."
Walton's innovations created thousands of new jobs and allowed millions of Americans to save money with the low-priced goods.
Brink Lindsey, an economist with the Libertarian Cato Institute, said consumers may be saving as much as $100 billion a year because of Wal-Mart's success in keeping its prices low.
"This translates really into a wage increase that Wal-Mart is offering to all Americans that shop there," said Lindsey.