The 50% of the albums being sold to the rest of the world was just an assumption, but even then I would not see the point in releasing it outside of Japan. When you look at just how big the rest of the world is you will realize just how spread out and small that market is.
I doubt many people think these are worth it, either. $40 for game music? Most people would just rather buy all of the games represented in the collection for way less and go to the sound tests in them.