I just came back from lunch with a friend. She left her ticket in the car so it couldn’t be validated. The restaurant gave her a slip of paper with a validation stamp on it. (It was a rubber stamp validation.) The rates are $11 per hour, $29.50 max. The validation was for time, and was for three hours. We stayed slightly less than an hour.
Assuming he had an IQ higher than room temperature, what did the cashier do? He took her ticket, charged her $11, and put the money out of his pocket in the drawer. The next person who came by with a full boat 3 hour $29.50 ticket he ran through with the validation, collected all the money, and put it in his pocket. Net to him $18.50. Not bad if he could pull that off eight or ten times a day.