Doesn't the funding source (BTC) make it at least a bit interesting? For example a card user in the US could have this credit card, and international relatives

Doesn't the funding source (BTC) make it at least a bit interesting? For example a card user in the US could have this credit card, and international relatives could fund it with BTC and not have to pay international transfer fees. It seems like a small step in the direction of using BTC as an actual primary account on the backend and making transactions in the real world.