Another thought is that a lot of cruises terminate on Saturdays and Sundays when banks are closed, which could account for a delay in releasing holds on the cards.
On one of our cruises, even though we gave our TA the card number we would use to do our fun pass, when we got to the VIP lounge to check in, we were set up as cash. It took just a few minutes to change from cash to debit card, but when they thought we were doing cash, they said we would have wait until we boarded and go to the purser's desk to set up our account. I sure don't want to do that - stand in line once I am on the ship.
Been there - done that:
2005 Holiday, Sensation, Conquest,
2006 Conquest, Celebration, Holiday,
2007 Freedom Grand Med, Holiday
2008 Fantasy & Sensation,
2009 Fantasy, Holiday & Dream Grand Med
2010 Fantasy and B2B Elation
2011 Monarch of the Seas
2012 Booked - Breeze from Barcelona 12 days