As of February 2018:
* New Castle / Wentworth by the Sea, A Marriott Hotel & Spa:
Weekend: as Gold received voucher for continental breakfast in the restaurant for 2 people. Option to upgrade to "Full buffet" for $5 per person, which basically meant using the same buffet and getting access to the omelette station and waffle irons. OR, voucher could be used for cash towards the regular breakfast menu. It did not have a dollar amount on it or specify this, but the waitress said it was good for approximately $31.52.
(Don't ask me why it would be that specific an amount, I have no idea. Went with the upgraded buffet personally.)