I was just on the Fantasy 2 weeks ago. The gifts shop would not take Visa or Disney gift cards. They told us to go to guest services and have it applied to our on board account.
Usually on board the ships it is the Key to the world (KTTW) card that you use for payment. I have never tried to pay with a gift card except to load it to my account at guest services.
Bumping this up to see if anyone has firsthand experience... considering buying each kid a gift card to allow some freedom but limit spending. This would seem to suggest it works, but I'd rather heard from someone who did it!
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