Although you can’t right-click on these folders, you can use the Tools – Add Current Folder to Places option.

For Revit 2014, it looks like this in the Registry, at path
HKEY_CURRENT_USERSoftwareAutodeskRevitAutodesk Revit 2014ProfilesAllAnavDialogs:

You could hypothetically populate these using a script or Registry merge (if you are careful).

Note: you do not need to restart Revit for these changes to appear.

My previous post about editing Registry Places:

In RAC 2011, we can not directly modify the display name for a ‘My Places’ entry in the Open dialog.
This needs to be done in the Registry, as described over at Do U Revit in 2009.
I made a brief video of this process (there is no audio).
  1. Open Revit, go to Open dialog, add a folder to the ‘My Places’ dialog.
  2. Save the changes.
  3. Close Revit.  (You may not even have to close / re-open Revit).
  4. Open Registry Editor.
  5. Go to [HKEY_CURRENT_USERSoftwareAutodeskRevitAutodesk Revit Architecture 2011ProfilesAllAnavDialogs] (for 64 bit)
  6. Modify the ‘PlacesOrderxDisplay’ for the appropriate index / number entry.
  7. Re-open Revit.
 Be careful when modifying the Registry – you can break things if you aren’t careful.