Hermit Crabs

I'm going to venture away from my furry pets early on here to talk about an "exotic pet" I had as a young girl: Hermit crabs.

(Photo credit unknown.)

My mom worked at a pet store, so that's the only reason I can think of that my brother and me wanted hermit crabs; we saw them at mom's work. (We had many fish tanks, too. I believe five in the house at one time.)
I don't specifically remember the desire to have hermit crabs, and today I couldn't tell you the proper way to care for them (and probably didn't know back then, either), but I do remember one thing about them:

(Photo credit unknown.)

Yes, dealing with them invoked a bit of fear in me. I would tentatively handle them for fear of getting pinched. Do hermit crabs get more tame with more handling? Generally speaking, I don't know. I know mine didn't. Not that I got pinched every time I handled them, but once was enough to make me well aware I didn't want it to happen again.
What I remember of them was that you needed to leave an extra shell in their aquarium/habitat so they could change shells. Presumably this was because of their growth. The other thing I remember was that when they died, they came out of their shell.
I believe I had several, then suddenly we stopped getting them. But for awhile, our house looked like a pet store.