At a time when prices are stagnating on everything from toilet paper to diapers, such pricing power for a product that is increasingly obsolete has confounded shoppers [Editor's note: the link may be paywalled] . "As far as the prices go, you don't have a choice," said Samuel Hurly, a contractor from Mount Vernon, N.Y., as he scanned a Home Depot display of AAA batteries to power flashlights he uses on the job.