When I related the conversation to my wife, she said, "Harsh." "But, True."
Well it isn’t free even if you don’t carry a balance - every store that accepts the card pays a fee for each and every transaction the card is used for. That’s why they entice you to use the card even more with cash back bonuses even if you never carry a balance. Those that do that not only don’t pay anything for the card, but get paid for using it.