To answer your first question, Yes, hop flavor will fade even when a beer is refrigerated. I don't know how the hops flavor changes in an un-refrigerated beer, but I would guess it is just as fast (or faster).
This even happens in your commercial beers. Hopslam and even the Elder's hop flavor (aroma and bitterness) diminished or mellowed after aging in the fridge. IPAs and such should be enjoyed young.