I like my local Giant grocery store for the most part, but they are chronically short on checkout staff. So even though I typically go to the store late on Sunday evening, the lines are usually still long, sometimes stretching back into the aisles. (A social norm has developed for these lines whereby at a certain point, it breaks off and the next person waits at the front end of the adjacent grocery aisle, so that there is a space for people to move across the front of the store.)
Particularly if I'm there in the last hour the store is open, I've often observed this leading to a situation where the checker is scheduled to close his or her register, and turns out the light, but the end of the line is too far away to say "I'm closed" to new people getting in line. The checkers often deal with this by talking to the last person in line and tasking them with making sure no one else gets in line. Clearly, this is not a very desirable position for the customer to be in -- you have to tell potentially cranky people to go to another line, and to other customers you seem kind of obnoxious for having taken upon yourself (it seems, anyway) the authority to tell people which lines are closed.
But I've drawn some amusement from watching how different people handle it. Tonight's installment was particularly funny, albeit in a very understated way. The checker walked back to where the last guy was standing and told him he had to be an end-of-line enforcer. "Oh, okay," he said. A moment later I saw him somewhat sheepishly turn away another guy who got in line, but no big deal. A couple minutes after that, however, someone parked an unattended cart behind him for a moment, and the checker called back "Hey, that's not somebody in line, is it?" "Uh, no, I don't think so," he said. (Being accused of failing at your line-enforcement duties...harsh.) Several minutes later, the line had moved up enough that he was no longer waiting in the aisle, and I watched him look back and see a different unattended cart parked ominously at the end of the aisle. The poor guy looked slightly stricken, and he shuffled back and forth for a moment trying to identify whose cart it was. Not having any luck, he kept glancing between the checker and the cart until someone returned and moved it.
At that point, I got up to the register, so I don't know if he had any more travails as end-of-line enforcer. But I would happily give up this small source of amusement in exchange for shorter checkout lines...