Consider this directory structure... drwxr-x--x 23 root root 4096 Jun 3 12:25 // drwxr-x--x 4 root root 4096 Aug 12 2010 /home/ drwx------ 5 user user 4096 May 11 19:31 /home/user/
The goal is to keep users from being able to see the other home directories on the system at all as well as even being able to list the things in the root directory.
However, mlocate sees the unreadable / directory and filters EVERYTHING making mlocate useless to users.
Since a user can list the files in /home/user locate should not filter them just because the user can't list the files in /home or /.