A couple of years ago my bank sent me a new debit card and deactivated my old one unexpectedly. I suspect this was because of the Home Depot hack in which the details of some 56 million credit cards were stolen because they were being stored for no apparently good reason on Home Depot's POS system. The problem was greatly magnified because Home Depot was not just using the card information to execute transactions. It was actually storing the customers' card details permanently without their knowledge or consent.
Has this event resulted in retailers changing their policies and not secretely saving copies of their customer's card information, or are retailers still engaging in this conduct? Are card issuers like Mastercard doing anything about this, such as making it part of their merchant contract that the merchant does not keep secret copies of customer cards?