Is it possible that you bought 2,000 extra miles at the time of the booking and not realize it? The Website gives two options to get more miles. Each option is $40 more. The first one is the 2,000 extra miles option at the time of selecting the room. The second option is the booster option. Given that you think taxes should be $30 instead of $70, just wondering if you ended up buying 2,000 extra miles during booking.