Fun fact: They apparently aren't connected to anything, and transactions are processed later, so basically any valid card will go through regardless of funds etc.
The market for shoddy bacon baguette & gin fraud is presumably fairly limited.
Cards however have a special "service code" on the mag stripe/chip. Certain cards like the Monese debit card or debit cards for customers who are not allowed to go into overdraft can only be used for online transactions. So they wouldn't work in this case where the transaction is authorized offline.
Source: My experience with cards in Germany where the train company is processing credit cards the same way.
I really wish I could find that video again. It was interesting.
I assume that first word isn't what you meant, but I can't come up with any substitute. What was it supposed to be?