Have you really read your cruise contract? A comment made me think... Acts of nature (ie weather or a hurricane) does not mean the cruise line have to give you a refund if something has been changed/delayed/missed...
I found this old article (2010) http://www.nbcnews.com/id/38792765/ns/travel-cruise_travel/t/clauses-beware-your-cruise-contract/#.V_vg0PkrLcs
which was interesting.
I found RCI's cruise contract and here is just a blurb: Except as provided in Section 6(e) below, Carrier shall not be liable for any claim whatsoever by Passenger, including but not limited to loss, compensation or refund, by reason of such cancellation, advancement, postponement, substitution or deviation.
e. In the event that a Cruise (or the cruise component of a CruiseTour) is canceled or terminated early due to mechanical failures: i) Passenger shall have a right to a full refund of the Cruise Fare if the Cruise is canceled in full, or a partial refund if the cruise is terminated early; ii) Carrier may cover or reimburse Passenger for additional costs (e.g. airline change fees) as deemed appropriate by the Carrier. iii) If the passenger has travelled to the Vessel Passenger shall have a right to transportation (by means selected by the Carrier to the Vessel’s scheduled port of disembarkation or the Passenger’s home city; and iv) Passenger shall have a right to lodging (selected by the Cruise Line) if disembarkation and an overnight stay in an unscheduled port are required due to the Cruise or cruise component of a CruiseTour being cancelled or terminated early because of such mechanical failures.
Would be a good "light" read if someone has never read through them.