I've not seen foundation wrecked by moths unless it was in a vacant hive
adjacent to drawn comb.  Certainly never seen the moths go at stored
foundation or unoccupied hives with foundation-only.  But maybe they would
if desperate(?)
 
Moth larvae burrow thru the comb and get norishment from the pollen in it,
and as far as i can tell it is the pollen which they are really after.
Once drawn out, all comb has bits of pollen in/on it from the constant
traffic and attention of the bees; also honey contains bits of pollen.  So
even extracting combs, clean and light, are subject to attack eventually.
However, leave some vacant combs around that have had brood or pollen in
them, and the grubs will make a mess of them in no time!
 
I've been busy placing the cleaned-up brood chambers from the dead hives
onto my strong colonies.  It will delay swarming preparations and make sure
those brood combs are safe and maintained.  Seen some scout bees lurking
around so maybe i can get some swarms for the rest of the empties!  I know
the moths larvae don't appear this early, but i sure have seen lots of
adults (greater and lesser wax moth) flitting around my empty supers the
past few weeks.  I'm sure they have eggs in there already...
Later,   JWG