I don't know about NZ specifically. But when talking about cash tickets, if an airline has an advert saying "fly to Hong Kong for $499 one-way" then it must be possible** to buy an entire ticket for $499 (plus credit card fee ), it can't be $499 plus a random amount we won't tell you until you click through to the payment page.

Therefore when it comes to redemptions, if an airline has an advert saying "fly to Hong Kong for 50000 points" then it should be possible to buy an entire ticket for 50000 points only. If the minimum cost is 50000 points + $100 then the advert should state that. Having said that, airlines don't usually advertise in this way. But if you have examples of misleading adverts, I would expect the governmental advertising regulator to take action, at least depending on how interested they are in pursuing a case.

Many loyalty programs are moving to dynamic pricing. In principle there's nothing wrong with having higher base point prices to/from HKG, Brazil etc as long as there is no misleading communication about it.


**Different countries have varying rules about exactly how many expected viewers of the advert should be able to purchase the ticket for $499 e.g. they can't stick up a billboard in the city for 2 weeks and only ever have had 10 seats available at that price. So in theory if airlines send out say a marketing email that mentions redemption prices (in J class) there should be more availability than 1 seat per year...