Say I'm a cashier at a retail location. All I need to do is say our system is down, carbon-copy-swipe your card number, CCV, and expiration date. You'll give me your Zip code and billing address when I ask for them "to verify the transaction with the card issuer later on when the system comes back online." I don't need your signature since that requirement is gone now. I can sell that CC info for money or I can make a few fraudulent purchases online where no card is required to be present.

Card fraud is embarrassingly easy in the USA if you're in the right position of employment, even in lower rungs of employment.