When we engaged in this same "tour" we got:
Mexico - churros
Norway - school bread
China - red bean ice cream (but I was pretty disappointed, as it came in the old school cafeteria, hard-as-a-rock, little tublet with wooden spoon) -- would shoot for an egg roll next time
Japan - Kaki-Gori (the snow-cone thing...very much enjoyed by the kids)
Germany - pretzel from the cart (just seem a lot better than the regular Disney pretzels)...but the nudelgratin and bratwurst from the quick service place would also be good; the Karamel-Kuche is also pretty awesome across the board...they once had caramel/chocolate covered grapes that were incredible, but they are gone...still like the popcorn and covered pineapple spear
Italy - might have skipped Italy....not a lot of snack options as I recall -- gelato, maybe, and Tutto Gusto is a good stop if you want to do slightly more than snack but not quite eat a full meal
Morocco - I convinced the family that a shwarma wrap was a snack...and it was great
USA - funnel cake
France - the bakery and ice cream shop are both really good
UK - fish and chips
Canada - tough one other than some sort of maple candy in the store....but as noted above, the Cronut just around the corner is close enough to be considered part of Canada if nothing in the store jumps out at you.
Since our official attempt at snacking around the world, we almost always end up back in Germany, France and UK.
