If you ever come to North America, you don't have to worry. In the worst case, you can almost universally get a cashier to void a sale here, but the only place I've seen DCC has been with the Verizon MX terminals. It was within the customer's complete control, and the cashier couldn't change the input.

On another note, I checked out of the SkyCity Marriott, and I switched the payment card at checkout. The lounge attendant had some difficulty understanding my request to get a courtesy copy of the receipt. This was up in the Executive Lounge rather than at the front desk. The lounge attendant initially had presented me with what looked to be a quote slip, but that wasn't right. He was finally able to get a courtesy copy after I used the magic word 'reprint'. This leads percysmith and me to believe that the SkyCity Marriott might be opt-in DCC, but I have no way to confirm. For reference, here is my receipt from one year ago:



And here is the one from January 18th:



The receipts look identical save for the first one was an offline swipe and this one was online chip, so I believe I successfully dodged DCC once again based on the OFFLINE-OPT/O# receipt with the higher batch number. You will notice that in the course of one year the DCC markup has gone from 4.4% up to 5.35%. Will it be 6.5% next year? It's appaling, but at least they seem to honor currency choices if you insist on it and get the reprint slip. I never trust "check the [X] local currency box, and it's local currency" phrase. In the future, I will check out at the front desk only since they seem to have more experience in the matter of DCC.