Since I am a Japanese music fans who are benefiting from bonus tracks. I have to say something about this issue.

As Danny says most Japanese releases have bonus tracks because Japanese CD is far expensive than imported disks. Take Britney's disk for example U.S. version is about U.S.$17 while Japanese version costs $26. Unless some bonus tracks are added they won't buy the CD. But in most of the melodic rock releases that is not the only reason because outside Japan melodic rock albums come from Indie labels who will not have enough funding to export to Japan endangering Japanese version and import disk is sometimes a bit expensive(such as Loverboy 6 which cost $30 in Japan). So there should be no reason for Japan-only bonus tracks. I suspect Japanese labels use bonus track as a way to clear off left over stocks.(Even though they didn't sell in Japan they can export as extra version tracks). But I don't think that sort of practice could be beneficial to serious MHR fans.

Some artists already know it and have no extra track for Japanese.

Just think of bonus track for gratitude for Japanese MHR fans and nothing more.

Regards

Susumu