RollyShed:
Bung:Not necessarily older, it's an Iwi preference whether to use a macron or double vowel. I don't think the IRD would worry about connotations.
So how many dialects are we talking about in this low population country?
NZers have an unusual expectation of language... that everyone speaks it alike, and that everyone can understand everyone else (with the exception of Southlanders' Rrrrr and crib/bach).
In Europe, there's generally a local dialect which will differ noticeably in pronunciation and vocabulary over a distance of (say) 20km or probably less. In England, there's a huge difference between how someone from Cornwall speaks and someone from Newcastle and someone from Glasgow. They probably would all have difficulty understanding each other (as would Kiwis). Most European countries have a "standard" language (think "Received Pronunciation" in English) that is taught in schools whilst local dialect is used for actual conversations between locals. My grandparents moved about 150km, and so had to speak "high Dutch" to the locals and were therefore considered posh and snobbish. Some (many?) people struggle to speak their "national" language.
Ironically, perhaps, low population density tends to increase language variability, since there's little chance of interacting with people with other dialects/accents.