I (an American) had actually never heard of Costco until I moved to Japan. Where I grew up we had Sam's Club, but no Costco, so when I got to Japan and the other foreigners were talking about how they love getting the chance to go down to Costco, I had no idea what they were talking about.
Didn't see a Costco in person until a few years later.
Similar, perhaps. I enjoyed visiting Costco in England and devouring jacket (baked) potatoes with Heinz baked beans (I'm aware this is Lemmy...), Shepherd's Pie and a hot cup of Yorkshire Tea - so the menu is localised too.
I don't remember if they also had the typical American fare when I was there, because I was more interested in the British cuisine I had missed so much. They may have had the froyo and hotdogs. Im certain there must have been pizza, surely.