Answer by James Schindler,
If a card was declined we would always tell the customer that we were having trouble with our machines and the card would not go through. We would say that it might not go through because they were from out of town. "You know how those companies are with fraud." We would never, ever use the word declined.
The customer would almost always have another card. If they did not, we would ask them to come back the next day and settle up. We were never burned.
Most of the time paying customer knew that the problem was on their end but we were willing to take the blame to avoid embarrassment.