well as a sort of semi ground-surveyr myself and knowing many "hard core" surveyers, I can assure, such law philosophy is akward and obscure. Sea surveying, expecially in EEC is completely another question and cannot in any sense claimed to be standard and harmless procedure. Just action would always have an "evil" purpose behind. But that doesent apply to basic land surveying, becouse all infrastructure, all construction, all areal politics, all real estate questions and many more cruicial fields of society depends on surveying that it is as common task as would be hitting a nail with hammer.
To think that it would require authorisation wouldnt even have crossed my mind untill this news.
Surveying your own land is one thing. Surveying other people's land at least requires the owner's approval, or it's trespassing. Surveying land for public use (road, park) is one thing -- although it would be wise to at least gain the approval of the local government. But to survey unopened, government owned land in the middle of nowhere (i.e. no legitimate reason for use), that's really asking for it.
Note this information, with reduced precision, is probably available from national cartographical agency. There is really no need to go acquire it yourself. If you require that much precision in the middle of nowhere, then your motive is suspicious.
Since this is paid by Japanese government, intelligence operation cannot be ruled out.