Regarding shortcuts for close/quit etc.: they are not always
wanted. When I'm recording live I don't want any single key
or mouse click to accidentally interfere with that. It's bad
enough with e.g. Ardour's GUI - every single pixel of it will
do something when clicked on, and the result is not always
so benign. I've had a musician dropping his shoulder bag on a
cable to a cardbus interface during a live recording. This
ripped out the card and destroyed the mechanical card locking
system. So having an accidental click or key pushed is not at
all such a remote risk.