Yet Chicago's Wrigley Field parking gambit is only the latest example of a growing movement toward surge pricing — the practice of making customers pay more during times of heavy or peak demand. Already, airlines and hotels are veterans at charging premium rates during busy times, but now — as high-tech sensors and pricing algorithms make it easier to anticipate demand and boost prices — many other industries are exploring surge pricing, including retail, ride-sharing, sports and entertainment venues, and maybe even health care.