I booked a one way rewards flight back home from Christchurch to Melbourne (to use some points up and also avoid the 6am horror flight with Jetstar). The Qantas website forces you to use its NZ site and quotes the taxes in NZD. I proceeded with the booking and the transaction on my credit card initially showed up on my internet banking site as a pending amount in AUD from Qantas Mascot. A few days later the entry on my statement shows it as Qantas Auckland and in NZD. My credit card then charged a foreign transaction fee for the conversion back to AUD. All because Qantas's website won't let you book one way to Australia from its Australian site.