Here in Sweden most people don't carry any cash and would buy a stick of gum with their card. If you want to give someone money, you "swish" it to them. Swish is a massive smartphone app for people to people payments supported by all banks.
If I were to guess how it works it would be like:
The receiver of a swish actually gets the money from their own bank while the sender actually just sends money this their own bank as well.
Then the senders bank will set a IOU to the receivers bank to balance things out and that will get fixed in a couple of days (the whole bank day transfers)
Prices may vary depending on at which bank the business/organisation opens an account and activates Swish to.