They're not moving when you put a nut on the end. What's the issue with this implementation of moving parts?
This setup is much more resistant than the above method to:
-Impact and deformation
-Heat - a thin piece of metal heats up much faster to ambient than a solid piece and has more surface to pick up radiative hea
It's not just about the extreme physical properties (which 2MM of 300 series SS would do very well).
Small parts get lost.
ie. How many times as you were trying to take out a stick nut the washer fly out and you couldn't find it?