No Thank You

"The hardest job kids face today is learning good manners without seeing any."
-Fred Astaire

Some months ago Spouse and I were in the supermarket for our routine of grocery shopping, a weekly experience for which we must take a deep breath and steel our nerves before embarking on.
Assuming that the task went along as it should- I am sure that it did not but let us proceed swiftly to the end- we made our way to the checkout. Spouse was signing the receipt when the cashier's code card fell at our feet. This card is emblazoned with pictures of all items and accompanied by codes for ascertaining the prices.
Spouse picked it up and gave it back to the girl on the checkout.
"Thank you," I said, loudly.
There was silence. The cashier packed our bags with a solemn expression. That is to say, no expression at all.
"No, thank YOU." Sadly, that was myself again.
"You are welcome."
"No, you are the one that is welcome."
By this time Spouse and I were in the parking lot and wandering away with our goods.
"Thank you..."
It is a terrible pity that the cashier could not have contributed even a little to the dialogue. The important thing is for us to not let it affect our own sensibilities and manners.