As the mega-sales ramp up for Black Friday, some shoppers will rush to the malls ready to spend. Others will stay home and pinch their pennies. Both groups, according to a growing body of research, will probably end up unhappy. "Some people experience this distress a lot, where they typically spend less than they would like to, they pass up on indulgences, they buy cheaper versions when they could have bought higher quality items, and they end up kicking themselves afterwards," said Scott Rick, a marketing professor at the Ross School of Business at the University of Michigan in Ann Arbor. "On the other end of the spectrum," he said, people "chronically spend more than they should and end up kicking themselves, too."