Agree $80K vs $15K car, not a good quality advertisement.
What is the difference between "rattles caused by insulation" compared to "clip rattles"????
Did they give you any explanation?
To me, a rattle is when something is lose and vibrating.
If an item is loose, then it can vibrate/rattle as you drive along.
WRT the insulation, the materials that I have seen are of a soft composition that should not make any noise if it vibrates if its loose.
Make sure that its not the loose parking money in the glove box. :)
Rattles are hard to pinpoint and can take hours looking for them, then, just a couple of minutes to fix.
Get it done under warranty as they may have a list of the same report by other owners..
Good luck.