Naive first cruiser question. I like to know details so I don't worry. We're signed up for the Island tour and Snorkeling with Stingrays in Grand Cayman, but hope to walk around shop afterwards. What happens to your bag while you're snorkeling/feeding the stingrays? Also, can you tag as luggage a case of water? Linda(DW) DH , DD15, DD12, DD9, DS6 Magic, 7/29/06!