We had a guy come into the shop right before close, I was helping him and asked the teenaged cashiers to turn off the OPEN sign once it was 9 so more people wouldn't come in.

9:15 I'm helping the guy and walk up to see 3 teenagers standing next to the open sign. They ask me "how do we turn this off?"

BY TURNING THE BIG SWITCH THAT SAYS ON/OFF TO FUCKING OFF!!!

Like are they actually this incompetent or are they playing so I don't expect anything of them? I'm leaning towards the former since this act of incompetence was actually potentially creating MORE work for them.