I'm fairly sure it's a reference to the generally disposable and fully encrypted nature of Chrome OS. There's no reason it wouldn't be password protectable and the link describes that the chroot can be encrypted as well.
To run crouton you need to put your machine into developer mode though, which could mean that all bets are off. (e.g. if you power it off, it comes back up without requiring a password, since this is annoying/unnecessary if you're actually developing for Chrome OS.)
Uh, no. I have had my Samsung ARM chromebook in developer mode since day one, and I always need to put in my Google password to log in, even if you are not connected to a network.
Same here, not sure what mjs is talking about.
Huh, I wonder what the crouton developer was talking about then. No encrypted disk? (I don't have Chrome OS, I was just guessing what the crouton README might mean.)
Further down in the Crouton Readme: "Note that developer mode, in its default configuration, is completely insecure, so don't expect a password in your chroot to keep anyone from your data. crouton does support encrypting chroots, but the encryption is only as strong as the quality of your passphrase."
Right but any gmail user can login too (and use your chroot).