This DOES work on a cruise ship. You don't actually use your credit card in the casino, but your "sea pass" or whatever that cruise line calls your room key/on board charge card. At the end of the cruise all charges are posted to your account and your credit card on file is charged one time for your total for the entire cruise...drinks, trips, spa, games, casino. Your credit card company just sees a charge from the cruise company and no cash advance fees are charged.