Why can't I Edit desktop file from Nautilus?

[Colin Law]

In ~/.local/share/applications are .desktop files.  If I view that
folder in Nautilus and right click one of the files then I get an Open
option but no Open With options so that I can open it in gedit (or
whatever) for editing.  Is there a good reason for this?  This is the
sort of behaviour one expects from an OS where the system assumes that
it knows best, mentioning no names.

I know I can edit it from the terminal, that is not the point of the question.

Ubuntu 11.04.

Colin