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shopboxes.
I would tend to agree with you that it appears as though they need to disclose the resort fee on that confirmation screen, however they also have a loophole. If you click on the "taxes and fees" link, you'll see this:
Depending on the property you stay at you may also be charged (i) certain mandatory hotel specific service fees, for example, resort fees (which typically apply to resort type destinations and, if applicable, may range from $10 to $40 per day), energy surcharges, newspaper delivery fees, in-room safe fees, tourism fees, or housekeeping fees and/or (ii) certain optional incidental fees, for example, parking charges, minibar charges, phone calls, room service and movie rentals, etc. These charges, if applicable, will be payable by you to the hotel directly at checkout. When you check in, a credit card or, in the hotel's discretion, a debit card, will be required to secure these charges and fees that you may incur during your stay. Please contact the hotel directly as to whether and which charges or service fees apply.
That tells me that there can still be a resort fee even if it's not disclosed at the time you pay for the room. Kinda shady if you ask me, but technically they've given themselves an out on it.