It's polite to say thank you.
Jenny is checking out at her local grocery store and receives excellent service from the cashier.
Jenny wants to decide how to respond to the cashier.
Jenny thanks the cashier for doing such a good job.
Jenny decides to pay and leave without saying a word to the cashier.
The cashier is happy that their hard work was recognized.
The cashier feels their quality service went unappreciated and is discouraged.