C.O.D.'s (Continuous On Duty) trips went very senior back in the 90's at USAir. You typically worked 10 of them in a month and you were done. For more than 4 hours between flights you got a hotel room.
There was an old joke about "How do you get a C.O.D. F/A into the cockpit? Grease the door frame and put a Snickers bar on the floor". F/A's loved the trips because they were very short flights with no service required. They rarely even got out of their seats.