You have to give credit to RCI for at least offering that much. They didn't have to. I doubt that 30% of a future cruise would make up the hotel nights and the flights to the next port, but its better than leaving them high and dry.
I think Carnival realized with the Splendor fire, that treating your customers well and compensating them fairly is much better advertisement than that same money can buy. It probably cost them a couple hundred thousand dollars to put those people up in hotels and fly them to the next port but how much does commercial time on national tv cost?
Carnival Cruise Lines:
Fantasy 90, Celebration 95, Victory 05, Conquest 05, Spirit 6/06, Freedom 6/08, Holiday 7/08, Victory 6/09, Valor 9/09, Dream 6/10, Splendor 8/10,Conquest 8/11,Magic 11/11,Triumph 4/12,Spirit 7/12,Freedom 11/12, Triumph 2/13 - The fire cruise
NCL Dream October 2006, RCCL Mariner OTS June 2007