Posted By:
warshawlawI've been known to bust out a card from one and send to the other for aesthetic reasons. Of course that's to get rid of PSA holders and put the cards into much more pleasing SGC or GAI holders.
Also, set registry. If I have a bunch of SGC graded cards from a set and want to do a registry, I'm going to cross over the odd GAI card that I might pick up.