A Sign of the Times?

I filled up my car's gas tank a few days ago and noticed something unusual: even numbers on each pump. I could discern the total amounts paid on about four pumps and the amounts ranged from $5.00 up to $20.00. None of the amounts were enough to fill up a tank, unless someone were driving a scooter or riding lawn mower. It seemed obvious that people were putting the amount of gas in their tank equal to the paper money in their pockets.

For some reason I felt a bit guilty when I swiped my credit card and let the tank fill to capacity.