It's easy to forget too that the history of credit cards was that they started as store credit cards, and centralized and inter-operated from there. When credit cards first started you would have one per store only usable in that same store.
(Also note how gift cards/stored value cards/"prepaid credit" cards recently seem to be following a similar trajectory. It is somewhat fascinating.)
(Also note how gift cards/stored value cards/"prepaid credit" cards recently seem to be following a similar trajectory. It is somewhat fascinating.)