So Klarna's business model is people missing payments on a regular meal? Does something similar work anywhere outside the US, or is this a US thing?

Like a credit a card, charge the merchant a fee. I think its around 4% which is why i am surprised door dash did it, usually on higher priced goods with more margin.

Klarna is a Swedish company, and is one of the biggest players in the online payment market in Sweden. Swedes can run up unsecured debt with the best of them. And yes, you've been able to pay your DoorDash equivalent in Sweden with Klarna for quite a while now, without it ever having made the news.