A French grocery store cashier wrote a book about her experiences which propelled her to fame and fortune.
“There are easy customers and less easy customers,” Sam wrote in a forward. “The rich and the poor, the ones with complexes and the braggarts, those who treat you as if you were transparent and those who say hello, the determined who tremble waiting for the store to open and those who show up regularly at closing time. There are those who hit on you, others who insult you. Who would say that nothing happens in the life of a cashier?”
I would like to read it, if it is ever translated into English.
My own experience working part time in a different part of a grocery store is that customers will make your day difficult, but a day without difficult customers is mind numbingly boring.