As you say "software seems better off" if proprietary: No, I don't think so.
It is however a way to make some income from the sales of the software.

I for myself can say I'm very happy if another coder looks trough my code, I know there
are plenty of nasty pointer monsters and other meanies around that are out to get me.
If my code was proprietary the software would be losing out as these accidents waiting to
happen wouldnt get fixed, they *would* happen.

-Harry