DS was pretty insightful when I got the box recently; he knows they aren't sending out the drives anymore, but they seem to be using up the boxes for them. Better than going totally unused, we figure. If you take the paper with Edna Mode on it out, you'll likely see the foam with the drive cutout underneath.
I use the boxes. They are cute and sturdy.
I've been trying to use the MB boxes, too. But they are both too large and too small, and so they remain in our "should we recycle it?" area.