Question re: index search order for desktop apps.

First - this is a fantastic app above all; what follows is a very minor curiosity.

It appears that gnome-do builds its index of desktop apps by scanning '/usr/share/applications/*.desktop' ahead of any entries in '~/.local/share/applications.'

Is there a specific reason for this? I figured it would be preferable to reverse the search order to respect overridden entries. eg - to preserve my geometry settings for the 'gnome-terminal' launcher, I could only do this by creating a new launcher or editing the gnome-terminal.desktop file in /usr/share/applications.