I wonder about that too. I'm a Dutch but bought my camera local here in the tropics and I have Arabic added for free as well .. lol. Well, I don't care too much basically as my brain is working English for more then a decade. Not saying it's perfect, but I tend to slowly forget my native language.
Looking at the languages you mention, it seems the 'international' version? I guess only for the Dutch they are equipped with the Dutch language, market protection and preventing grey import.
The English is not so bad though, you should be able to get the hang of it fast. Else, you can always ask me for a translation!
Good luck / Groet,