Thank you very much for the information, Walter!
For me, having a (small) label, export to (small) Japanese "import" retailers is quite attractive as they are ready to spend a bit more even on newcomer releases - provided the quality is high - than, for example, US or other European retailers will. - In imports of releases which are not regularly distributed in Japan, the 'added bonus feature' is no requirement, of course.
In general, I will admit that bonus material (songs, Japanese lyric sheets) is an interesting alternative to import taxes, economically speaking. ... If only we other nations didn't have to wait for a band's anniversary ere they scrape their bonus tracks together for a - ever too often incomplete - celebratory release. *sigh*
Thanks again and best regards,