The cases are smaller in Japan, but if they had the small cases over here, you know it would just be more ammunition for the N-haters to say that the Cube is kiddie "Look, the games come in these tiny cases because it's for little kids!"
Ugh.
But, at any rate, I'm afraid to use any kind of mass holding case, because it might scratch up my disks. I like the cases lined up on my shelf anyway. Looks kewl...