I can only speak for Canada, but Transport Canada allows NEF’s to be put into the MEL for the exact reason outlined in the first post. The situation had presented itself too many times in remote locations where a table tray or ashtray broke and suddenly the aircraft was grounded, often for days at a time.
In some cases an NEF is included as part of the MMEL (e.g., Q400) or it added after the operators flight and tech ops departments meet with Transport to come up with the applicable language. I’m surprised other regulators don’t permit this, although maybe it comes down to differences in the way other governments handle MELs and deferred defects.