Now try sending that money overseas. Depending on the countries and currencies involved you may be in for a world of pain (personal experience). It's great if you don't have that problem, but once you do you start to really see how arcane, bloated, and inefficient the current systems are.
The competition is P2P interbank transfers, which are being rolled out to be free in the U.S. (And are free in Europe.) Credit card transactions come with additional perks for the consumer, like anti-fraud and rewards, which bias the coin. Someone not caring for those protections can, again, use interbank transfer.