Stop ubuntu ask password on shutdown

 sudo gedit /usr/share/polkit-1/actions/org.freedesktop.consolekit.policy 

edit this section


    Stop the system when multiple users are logged in
    System policy prevents stopping the system when other users are logged in
   
      no
      auth_admin_keep
   
 

to:



    Stop the system when multiple users are logged in
    System policy prevents stopping the system when other users are logged in
   
      no
      auth_admin_keep
   
 


also check restart


 
    Restart the system when multiple users are logged in
    System policy prevents restarting the system when other users are logged in
   
      no
      yes