Earlier quoted context omitted.
Are you sure? I thought they cached login stuff locally so you can sign in while you're offline. Not sure though.
I admit that I don't have a Chromebook in front of me to test and that I'm not sure. This comment will likely be stricken from the record.
Contrary to popular belief, ChromeOS devs do know that people might want to use Chromebooks on airplane or train trips without network. Google Docs / Sheets / Slides work on a cached copy and sync when online again.