I think we pretty much live in a prepay world:

• You have to pay for gasoline before you pump it.
• You pay for your groceries before you leave the store.
• Laundramats make you prepay to wash your clothes.

Pre pay meter - This is a General Electric IP-3, that was manufactured between 1906 and 1908. The IP-3 was a redesign of the IP-2 using the Form 4 prepayment device instead of the Form 3 device. The IP-3 had the knob mounted on the prepayment mechanism, but any strain on the knob was prone to damage the mechanism, so it was soon superseded by the IP-4 which had the knob in the cover and had a notch on the back that operated a lever on the mechanism. The space above the register in both versions was for a scale showing the number of coins remaining to the user's credit.

"Coins to you Credit Meter"

Directions for inserting your coins

Coin slot