At my old work we had a buzzer system for collecting meals. The amount of times I'd explain to people on returning there change that it would vibrate when it was ready, only to have them come up and tell me it was flashing was ridiculous. Why do you even bother wearing ears?!!!

On one occasion a colleague of mine was handing out meals, a lady came up to the service counter with the following;

(I should make a note that we use recycled, non-bleached serviettes. They are a light brown colour)

"Hello mam, can I help you?"
"Napkins?"
"There should be some on the Cutlery and Condiments Table on the wall behind you."
"Oh, I looked, there aren't any there."
*Turns to kitchen* "L-----, I told you to restock the serviettes!"
*From kitchen* "I did!"
*Turns back to customer* "There should be some in tower on the table. But I've got some here as well."
*Offers a basket of serviettes to customer*
"...But, they're brown"