I live in the SF Bay Area, and three (so presumably all) of the Costcos here sell Mexican Coca-Cola in bottles (real sugar, not HFCS). It's great, if a little pricey (something like $18 for a case of 24 12-oz bottles).
I'd imagine the access to the CA wine country makes the local selection of wines better/cheaper than other parts of the country, and there's a pretty good assortment of fresh seafood available.
While on vacation on Kauai, the Lihue Costco had a cold case setup where they were selling different types of
poke, as well as fresh ahi sashimi plates, and many fresh local fishes (ono, marlin, mahi mahi, and kanpachi IIRC).
Where do you live, and what does your Costco have?
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