Chris Knezevich used to be a bartender and likes to tip generously, especially during the holidays.
Besides a standard tip, he'll soon start bringing extra cash to his favorite restaurants.
"At Christmastime we like to pay it forward," said Knezevich, an instructor at the College of Hospitality, Retail and Sport Management at the University of South Carolina. "We may bring $100 and we'll leave that $100 tip as a Christmas bonus."
