To use @ the beach, yeah, maybe. But for use @ the ship's pool(s), I'd say no. Honestly, I wouldn't bother bringing them b/c to me it'd be too much hassle to pack and then have to haul to the beach on excursions.
Can't find them on the "prohibited" list but I still think they would be an issue since adults are seated around the pool. I would not let my kids bring them.
As PP said, I wouldn't do it either. The area around the pools is small and filled with people. Some of whom don't want to get wet. It would be difficult to control where the water was going, IMO.
I wouldn't want to have to worry about packing them (and the possibility that they would get broken, what with the way luggage is handled).
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