Like you said, each store is different.
In my youth, I worked at LL and FC. At both, the bulk of wines were stored in store rooms that would get extremely warm during summer, so much so that we used to leave the loading bay roller doors open almost every day just to get some air flowing through the place.
FC had a premium wine room adjacent to the cool room which was temperature controlled. Most wines that were $50+ would be stored in there, although if we had too much of a particular product, they would be stored in the store room.
Again, this isn't an issue if you're talking about a small store that only orders enough to fill the shelves (which is what typically occurs with a lot of slow moving, premium wines), but as you said, each store is different.
