Christmas lines are illiquid

Michael Santo reports on Christmas lines:

As you wait in the checkout line just before Christmas, your observation is correct. That other line is moving faster than yours. That's what Bill Hammack (the Engineer Guy), from the Department of Chemical and Biomolecular Engineering at the University of Illinois - Urbana "proves" in this YouTube video

Sure, because the cost of optimizing the check out infrastructure for Christmas is more expensive than allowing long lines. In an illiquid queue, the next arrival changes the wait times appreciably, you are in the longest line because you just now entered the queue. Wait until two customers are served, look again and you will not be in the longest line.