Comment 7 for bug 506876

rsync tries to set user/group/right as the surce. If you are not root that you backup an item that belong to 'root', rsync will not be able to set destination file owner to root.

This is happens all the time event on a linux fs. Ex: if you backup /home/user/abx.txt
the '/home' belong to 'root' but '/home/user' and '/home/user/abc.txt' belongs to 'user'.

BIT also makes snapshots read-only.
To restore things right BIT keep a special file with this kind of information.