I was there at AutoZone the other day, and they did not have a great selection of the Gold Class products, maybe 4 or so (don't remember which), but no UP, and I don't even remember seeing GC car wash.
Advance is the only place I have seen UP on the shelf. They seem to have more of the newer products. They are the only place I have seen the hand-only Rubbing Compound and Polishing Compound on the shelf too. Their selection and price seems to be better than the other auto part sores.