Years ago when I was very young, not as young as I am now, but still pretty young – I often thought that when store clerk swiped the card at that “magic credit card reader” money somehow manage to get transferred into cash register through the wires. Only recently, after acquiring merchant account for my own purposes had I found that purchase by credit card is indeed a credit given by merchant, since he gets the funds with significant delay. In fact the delay could range from 3 days to a full month.
Updating bank info at credit card processing company can be a real pain in all the places you can think of. In my case – it is.