If that’s the extent of the time someone’s spent here in the last 3 years, they don’t live here, so why should they be allowed to vote here? It's not like the outcome of the election affects their day to day life.
I feel we should be doing everything possible to encourage people to vote - both by helping them feel engaged with and informed about the political process, and by widening rather than restricting eligibility. It was very heartening being at the New Zealand embassy here in Berlin with five other New Zealanders all of whom felt strongly enough to vote from the other side of the world.
For myself being overseas has not diminished my attachment to the New Zealand political process. A major reason I flew home earlier this year rather than next year (which would have been financially easier) was to ensure my eligibility.
All my close family and most of my close friends are still living in New Zealand, and though I now keep up with politics in Europe, I still feel I know much more about and am more invested in New Zealand politics.
I'm am informed about, attached to and invested in New Zealand society - but can't for now physically live there. I damn well want my right to vote.
Another important point for the expats is that they can enrol to vote up until the day before the election and can enrol unless they have not visited NZ in the last three years.
That of course applies to people in NZ but when overseas it is easy to just think one isn't elligible to vote - no nice people with clipboards canvasing for enrolments.
The enrollment is very painless these days and can be an email of a scan of the voting papers (which can themselves be downloaded).
Thought it worth noting since I was very depressed for a period thinking that I'd missed the boat with my overseas enrollment.