(A customer comes up to me with a can of table salt.)
Customer: “There’s no expiration date on this.”
Me: “No, sir.”
Customer: “But how will I know when it goes bad?”
Me: “Um, it’s salt. It doesn’t go bad.”
Customer: “Nonsense! All food goes bad!”
Me: “Sir, salt does not go bad. It’s a mineral.”
Customer: “It’s food! It goes bad!”
Me: “Sir, it’s a rock. Rocks do not go bad.”
Customer: “But it’s food!”
Me: “Yes, sir.”
Customer: “So when is the expiration date?”
(I give up and take the can from him, pretending to look for an expiration date.)
Me: “Ah, here it is.”
(I point to the UPC code.)
Me: “That’s the expiration date. As you can see, you’ve got a good twenty million years or so before that happens, so you don’t have anything to worry about.”
Customer: “Thank you.”
(He walked off with his can of salt, muttering about how it was going to go bad before he could use it.)