These devious cheapskates may foot their fair share of the bill all right, but where they pinch pennies at your expense is on the group tip. How? When the gratuity rolls around, they've only got some outlandishly large bill. To avoid any postprandial unpleasantness, at least one kind soul in your group will always toss in for them, thereby letting them off the hook -- again. In reality, the chances of any of us being stranded without tippable denominations more than once a year is approximately the same as our odds of besting Tiger Woods at Augusta.