when i was on a very small island in Thailand, i discovered that there was no shells there.
so that, the so-called 'naked crabs' had no houses.
normally they would find small shells, use them as houses and carry them around.
because they couldn't find shells, those hermit crabs would go into Nivea containers that tourists would leave on the beach, and carry them around on their shoulders as if they were their houses.
i found it so sad that three hours later, i took a boat to another, bigger island, where natives were selling shells.
all day i was trying to teach one particular crab to take off the Nivea container from his back and put on a real shell, but every time he went back to the container.