Trip, maybe a call to the embassy is a good thing to do?
It's an interresting question since we do the Magic in september, and googled on our ID requirements, being European.
I dont know the rules for cruisepassengers according to visa and such.
I do know that when ID is required by any authority (if it happens
) a photocopy of your passport is not valid in Europe.
In some cases when using creditcard in shops, they can ask you for a passport, usually the bigger purchases.
But then again, you might not encounter all of this
Make that call or send email to be sure!