Sorry, and with due respect to you, THAT is false. What is in the online store as defaults and what are carried as stock items in the store are NOT one and the same. There are certain build-outs of higher end models that, while not a "default" on the online store, are always sold as a "pre-built", in-stock SKUs in the stores. Two Apple store employees confirmed this for me without hesitation....
Now, it's possible that this is something (i.e. exactly what models/builds) that varies by region based on buying trends. That I can't say with certainty because I've never been to any stores outside of the several in my region.
Exactly. My AG 15" is the one of the is pre-built SKUs that are not purchasable from the online store. Refurbs are, in my opinion, completely random.