Obviously this is about the power outage in Spain.
While normally, if a card declines, people would probably have to leave their IDs with the restaurant while they went to get a withdrawl from their bank; this is a power outage, withdrawls wouldn’t work. It would be silly to arrest people because of a power outage. So I’m assuming people just have to give the restaurant owner/management their identity info with a promise to pay?
And power outages shouldn’t affect buses, since they run on gasoline/diesel, but the payment system processing transit passes might not work. Do buses still get run during a power outage and they just let people on for free, or do they just shut down the bus lines?
FYI, this is one of the major reasons to use digital wallets. Like Apple Pay and Google Wallet. They don’t use your actual card info when paying, but a generated virtual card instead.
Likewise one of my accounts provides both a physical card and a separate virtual card, so that’s what I enter whenever making online purchases. Easier to cancel and reissue a virtual card if there is fraud.