At Disneyland, a rope barrier folds a long wait into a tight weave of switchbacks.
The bends do more than save space: they hide the line's length, and a wait you never see whole feels shorter. They also let one entrance feed several counters, so you walk to whichever opens first.
The single line also ends the race between queues, where the neighboring checkout suddenly looks faster. Nobody picks a lucky line, so nobody stands in an unlucky one.