Repost of what I wrote on topics related to TOS bonus tracks:
The Japan situation derives from an old situation. It's a little more complex than what some of you are thinking.
Japanese record companies are an important factor in every record deal. Even if their power has faded, they still retain much muscles in the financial advances they make to an artist, a label or a producer. Note that these advances are at the core of any deal in the recording industry.
If you add to this that the big Japanese market is completely deregulated, you have the explanation: for they can't strike exclusive deals or preempt their own market, labels in Japan could be completely dethroned by imports.
So, in order to get sales, they offer their financial power in exchange for special releases (bonus tracks, packaging,...) that they can manufacture locally. Imports lose their pricing edge and Japanese labels get their own kind of exclusive deal.
It's interesting to know that when they had even more power, these labels got the possibility to get very advance releases of some albums, sometimes more than 2 months in advance ! It was another kind of exclusivity. With the p2p-days in force however, this happens less and less.
Hope I was clear.
Cheers