I don't know anyone who thinks the cards save them money anymore. People are tired of cards. Requiring a card to get sale pricing is something that needs to go away at the present time when physical stores need to make things as easy for the customer as possible, not something to implement at the present time and play off as some sort of innovation. Some people enjoy the gas rewards though I suppose. Kroger obviously wants the shopper data and knows the only way they can get a majority of customers to use the card is to force them to in order to give them sale pricing.
When Kroger (et. al.) started using cards, it was to get shopper data, which was needed as a lot of people were still paying with cash or check at the grocery store. With credit cards you don't need an additional card.
The fact that Albertsons is keeping the card at the Safeway stores confuses and infuriates me (and it is different than J4U), as getting rid of the card was one of the best LLC-era moves.