Google Drive – Can Other Gmail Users Access My Files?

I have had this problem and find that it is resolved by having those denied access to hit the "request an invitation." Once you invite them the second time it works. This happens every time I had collaborators without a Google account and has worked successfully.

The gdoc and gsheet files are, as you've discovered, simply pointers to the online version(s) of the file(s). (This only happens if you have the Google Docs app on your PC or Mac, of course.)

The only way to make local backups of the files so that they contain your actual data would be to convert them to a different format. Converting a gdoc to a Word file and keeping it in the same directory would give you what you want, but converting files certainly isn't automatic.

Is it necessary, though? Google Drive/Docs is already keeping revision information, plus anything you delete goes to the "Trash" and doesn't get really deleted for 30 days (at least).

Of course, things might be a bit different for Google Apps. Certainly part of your agreement with Google is the ability to get to backups of your data in cases of vandalism/hacking/etc., no?

You might also look into the Data Liberation Front to see what data you can extract, although I don't know if that would be useful in your case.