Oh. So that's the deal with the Outfit Shop. Here I was thinking the problem was just that people were selling items in bulk and hitting the regular MP cap.
Doesn't make sense that the outfit cap hasn't been raised now that a single item could sell for a couple hundred billion. But damnit I'm gonna be optimistic and think they haven't gotten to it yet since raising the caps on MP prices and what you can have on your account wasn't expected to go smoothly.