a) Are so clumsy you can't strip your own Plus
b) Want to make sure the signatures are really legible (some cases seem more legible than others)
c) Just plan to put the empty shell on your shelf.

Other than that, though, it had me ROFL. Especially since you usually can't sell a complete working Plus on ebay for that much.

On a related note, I was pleasantly surprised recently to learn that the IIci also has signatures. I'd never heard reference to that before.