BOOKED BEFORE FEE BEGAN? STILL CHARGED?

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The "grandfathered" practice.
You book your rooms in advance.  The casino imposes a fee after you book.  What places will honor the original booking and remove the fee:

THOSE WHO WILL GRANDFATHER

• Monte Carlo added a resort fee between the time I booked and the time I checked in and I was grandfathered. NYNY and Mirage also grandfathered people with reservations before the fee was instituted.  Viva Las Vegas
• Station Casinos will grandfather as reported by a worker at Aliante Station.

THOSE WHO WILL NOT GRANDFATHER

• Circus Circus, according to clerk when I phoned.

Looking for more information on this.