Good point, the update feature allows amazon to run defacto checks of the software your Kindle is running.
You're quite right of source, but I was actually considering how one might install a patch to the OS when there is no command line. As we've recently noted, the manual update process copies a binary file to the root then the OS recognizes it and enabled the update function. That's the only way I could think of.
EDIT: Before some Mod jumps me, I'm not suggesting a method of hacking the Kindle; just discussing why a hack to create folders isn't likely.