As for myself after having been on 28 cruises I just find any quiet and unpopulated
area (away from the road) and take my things off! And if told to put my bathing suit back on I would! I even started a trend while on the Grand Princess. When we stopped at Princess Cay my friend and I layed away from all the activities and off came my clothes! Well the crew also lays in this same spot and upon seeing me nude some also did the same ( or topless) you know the saying all for one-one for all !!!
But I would not recomend this for solo women it could bring unwanted attention or trouble.