The only positive aspect I see on these desperate issues you had is this: As Hyatt’s T&C are specific:

1. A "Competing Rate" is a publicly available and immediately online bookable room-only rate for a Hyatt Hotel that is lower than the room rate available for the same reservation on www.hyatt.com (i.e., same hotel, same type of room, same number of guests, same dates of stay and same length of stay). There are two notable exceptions*):
   
   • Opaque Travel Inventory
   • Any HVC or any residential or extended stay apartment property does not participate.
   
   
2. To qualify for a 20% discount on “Competing Rate” (and to receive stay credit within GP) we have to call either prior to or within 24 hours of booking the reservation on http://www.hyatt.com.

If an associate excludes booking.com - Europe’s leading online hotel reservations agency by room nights sold, is available in 24 languages and offers over 73K hotels in 71 countries (parent company: Priceline) – because the rate is displayed differently s/he is out of touch. Booking.com is very specific what is and is not included in the room rate and lists this immediately below the room type. While it’s habitual that taxes are included in Europe, the contrary is true for North America.

I hope Hyatt’s Consumer Affair’s department will investigate.

*) Package Holidays & packaged Rates are not Room Only Rates. Qualified Discount Rates & Unpublished, Negotiated Rates are not publicly available.