Zimco Restaurants v. Bartenders Union (1958) 165 Cal. App. 2d 235 involved a labor contract, apparently of no express duration, with employees of drive-in restaurants. The court declined to imply an intention of an indefinite duration; writing in 1958 with an astute prescience, the court noted: "It is difficult to conceive that parties dealing with the business of drive-in restaurants intended a contract to last forever. The history of technological developments . . . in the organization of American industry has produced a modern miracle where change, not perpetual status, is the order of the day." ( Zimco Restaurants v. Bartenders Union, supra, 165 Cal. App. 2d at p. 239.)