There aren't 8 subdivisions in an octave in western music either. Well, there are in any given scale, but there are also many scales. "Octave" is a misleading term. Given that it's just a doubling of frequency, the term is sort of as good as any other, and that douibling exists in pretty much all cultures that have developed string, pipe or other resonant body based music (including hitting hollow logs and plucking vibrating reeds / sticks / tines).

It's pretty much the foundational idea of any modality. No matter how you divide it up, the purest harmony is doubling or halving.