The newspapers tell us that Wal-Mart is going to start purchasing and selling "fair trade" coffee. That certainly seems like a good thing, though it's only natural to be suspicious here. Wal-Mart's whole business strategy is to reduce its prices by pushing some of the true costs of its products onto other people—paying workers below-living wages, pressuring its suppliers into lowering their labor standards, forcing customers to drive longer distances to get to its stores, violating environmental laws, etc. etc. But "fair trade" is predicated on the idea that corporations—and customers—should pay the full cost of their products.
Presumably something has to give, no? Perhaps in the future Wal-Mart can reduce its prices on "fair trade" products by lobbying to weaken regulations governing what can count as "Fair Trade Certified." Maybe not, but that seems like a reasonable thing to worry about.