SO I am all about the joke. No, really. I like to find them in daily life. Like in a busy restaurant, the waitress comes to the table and says "Sorry about the wait." And I grab my belly and say "Oh, me too, but I am working on it."
Well at retail stores, I usually use a credit card. IN most you insert the card in the reader, and it says "DO NOT REMOVE CARD" for a moment or two. Then it approves and asks if I want a receipt or something. SOme have a page that says "wait for cashier". SO I looked at her and said "So when do you get off tonight?" Today, the store clerk stood back a little and asked "Why do you want to know?" Oh.... "Well it said 'wait for cashier' and I wanted to know how long a wait I had.' But I think she was pretty creeped out. SO maybe I'll retire that joke.
Too bad, I kinda liked it.