" The switch from sales ladies behind each counter in five-and-dime stores to checkout lines, from waiter-served to self-service and fast-food restaurants, from full-service to self-service gasoline stations are among the responses to higher labor costs. So, too, are the absence of movie theater ushers and the wide use by restaurants of plastic utensils and paper plates, because they do not require dishwashing. "

― Walter E. Williams , Race & Economics: How Much Can Be Blamed on Discrimination?