Just came back from Japan, was pleasantly surprised to get 10% discount to buy some souvenir candies from the ANA Duty Free Shop in Narita airport using the Explorer card. On top of that, there's no sales tax. I would have to pay 8% sales tax if purchase from other stores in town, sure I could also claim the tax back if I purchase from a tax free shop, but that would mean a minimum purchase of 5000 yen as well. No such minimum from the ANA Duty Free Shop.

I am not able to find this 'benefit' listed anywhere in the Explorer card benefits list, but found in

https://www.anadf.com/en/otoku/

that "United Mileage Plus related Gold, Platinum, and Diners cards" all qualify for the 10% discount. Not really sure how they consider the Explorer card as a Gold or Platinum card. Wonder if the AF free TravelBank card would qualify as well.