Mental_Floss has an interesting little list making the rounds (in case you didn't know, the future of journalism is here, and it is lists, lots and lots of lists): 11 Things Wal-Mart Has Banned.
One of the items stemmed from a complaint at a Miami Wal-Mart in 1995. The mega-chain was selling T-shirts with a character from Dennis the Menace proclaiming, "Someday a woman will be president!" According to news reports at the time, the store had sold about two-thirds of the shirts before a single Miami misogynist complained. The store pulled the rest of the tees, and an exec in the corporate office declared that the shirt's message "goes against Wal-Mart's family values."
Somewhere Hillary Clinton was surely fuming. Meanwhile, Sarah Palin was running for mayor of Wasilla, where she would enact policies ironically credited with bringing Wal-Mart to the town.
Also on the list is an incident where Canadian Wal-Marts got caught selling Cuban-manufactured pajamas, which caused an uproar in the States when Wal-Mart execs decided they couldn't sleep soundly at night in their commie PJs.