Ownsnofins?
Flipper's a porpoise. Them things down there on your feet are fins. If you rinse them off--and there are rinse tanks or hoses or something at every resort I've seen--they won't have any sand on them. And they dry. Well, unless you buy the Nerf fins, but I find them slow and kind of mushy in the water.
Good advice to buy your own gear if you use it even occasionally. You can pay $60 for a set or you can pay, easily, over $250, depending on what you choose.
Whatever you do, rinse the sand (and salt) off once you're finished. They'll last a long, long time if you do.
