So in real life we all have our bank accounts other wise this game would not be running.
So why not add another real life feature and have interest earned on the money we have in our CC banks.
Yes i know the bonus of banking is that no one is then able to steal that cash for you, but for all the savers out there this could potentially be a good idea and be a better mod than some of the others we are seeing and might be a refreshing change.