1. It's the morally right thing to do.
2. It's good advertising. A lot of people are going to love this and banking is pretty competitive.
3. The decision could be reversed or someone may make the judge a better offer.
BB&T could be taking this stand for any one or combination of reasons. I prefer to do business with people who will turn down morally wrong business whatever their reason for doing so. It is not just right, but if they deal fairly with all people, aren't they the ones you want to trust with your money?