It is good to be courteous to other people
Bill has stopped for lunch at a fast food restaurant, which is a bit busy; the clerk looks quite flustered.
Bill wants to get his lunch quickly and get back to work.
"Bill smiles at the clerk and says, ""I understand you're very busy, I can relate to how you're feeling""."
Bill thinks the clerk is too slow and makes snide comments out loud.
The clerk calms down a bit and remembers to put everything in the bag.
The clerk is even more flustered, and forgets to include napkins and ketchup in the bag they give Bill.