Have been on 3 cruises, in a suite, and have always put our luggage out the night before our last night.  Of course, this means keeping night/morning supplies and clothes, carrying them through disembarkation, and getting all back into suitcases before the airport. It seems easier to keep the luggage (one bag, on wheels) and roll it out with us when we disembark.  Is there a reason not to do this?  A rule? A customs thing?  Does it slow us down at the port exit?