Western sanctions have disrupted nearly every part of Russia’s financial system, but there is one big exception.

The domestic-payments system continued to work smoothly after Visa and Mastercard pulled out earlier this month. While the card giants’ exit from Russia was viewed as a significant move by many in the west, the reality on the ground was anything but. Most Russian consumers never lost the ability to use their Mastercard- and Visa-branded cards to pay for things within the country.