Boston isn't the only big city into which big box chain Wal-Mart hopes to expand. In the past, the world's largest retailer has shied away from establishing outlets in urban centers. But the struggling economy has caused the company to rethink that strategy, since more and more low-income city dwellers are looking for jobs and cheaper shopping options — and fewer activists and city officials are willing to fight the encroachment.

But while the mayors of Washington, D.C., and New York City are welcoming Wal-Marts into their cities, Boston Mayor Thomas Menino is telling the company to move on. âThe problem I have with Wal-Mart is what they do to small businesses," Menino told the Boston Herald this week. "Wal-Mart makes their money and runs to the Midwest and deposits it in the bank. I want the money to stay in our neighborhoods and employ neighborhood people."

In contrast, New York City Mayor Michael Bloomberg defended the company's right to expand into the city as many members of the city council attacked it:

Mayor Michael R. Bloomberg, who has said that New York should be open to any legal business that wants to come here, was asked by a reporter on Thursday about the hearing and if it was in the cityâs best interest to let Wal-Mart set up shop. âYou should let the marketplace decide,â he said. âAnybody who has tried to manage the marketplace, it has not turned out very well. I think the Soviet Union is as good an example as youâd ever need of that.â

And the District of Columbia's newly elected mayor, Vincent Gray, offered words of support days before his swearing-in, although he said he would insist Wal-Mart pay âcompetitive wages ... $12 and up with benefits is fair.â

Menino's outlier position has rankled Herald columnist Michael Graham, who wrote today that he'd "like to hear the mayor explain to struggling families why the falling food prices that arrive with every Wal-Mart are a bad thing."

"Effete Boston liberals hate Wal-Mart, the unions hate Wal-Mart, and so Menino does, too," Graham added.

Although it's not entirely clear that shopping at Wal-Mart pays off for low-income residents who make up the stores' main clientele. An academic study released two weeks ago links the stores to higher obesity rates:

The research showed that one new Walmart for every 100,000 residents lead to an "average weight gain of 1.5 pounds per person....over a 10-year period dating from the store's opening," reported Shannon Proudfoot at the Montreal Gazette, in addition to raising the rate of obesity by "2.3 percentage points." That means that "for every 100 people, two who weren't obese ended up in that category after a superstore opened."

So, in other words, buy cheap food today and you might have a higher chance of developing health problems tomorrow -- and paying in medical bills whatever you saved at Wal-Mart. If the study is true, It seems to be a lose-lose scenario anyway you look at it.

Photo: Robert Sullivan/AFP/Getty Images