concordnz: Ironically the 'repair' itself has been provided to you free of charge already.
(it's just the travel and re-installing which has been charged for)
If you lived on the Chatham Islands, would you still expect the plumber to fly over there and back for free?
(you might get a discount for being polite in your communications with them, that is a Plus to your benefit.)
Everything you have said on this topic is hogswash. For a start, if the Chatham Islands are part of New Zealand, actually, yes you would expect them to fly over and back to perform the repairs at no charge to you if necessary. The manufacturer or retailer is responsible for covering the costs of meeting their legal obligation under Consumer Law. It is not a "plus to your benefit" to not pay charges you are legally not permitted to be charged.