When you pay by card in a Norwegian store, you probably use a card that supports BankAxept (since 1991). In that case the payment will be made through the banks, instead of through Visa. 3 of 4 payments go through BankAxept.

Cards issued by banks will often combine BankAxept and Visa/MC on the same card, so that users don't need a separate Visa card. The terminal will switch to BankAxept if available automatically. This is done transparently, so there are no issues with using it as a Visa card outside Norway.