Different availability or legality of British or Canadian products/ingredients. I live in Ontario and can get Irn Bru anytime. I know Americans don’t have ketchup or dill pickle chips for example. Also certain Cadbury products or Kinder products. Crush cream soda is exclusively Canadian and was the first cream soda I’d had as a kid. I wasn’t sure if all cream soda was Canadian.

Besides, they makes tons of food products tailored to specific regions. McDonalds menus vary from country to country as an example. Not only that, but ingredients legal in the States may not be legal in Canada or Europe. Americans don’t have unpasteurized goods available like cheese or honey, so yea things do taste different depending where you are. Mexican coke is sweeter than American coke. Canadian candies dont use the same dyes as American ones. American chocolates use butyric acid, so Brits think it tastes like vomit. If you’ve never eaten pizza in Naples, someone from Naples might tell you that you have never tasted pizza. An Irishman will swear that Guinness not only tastes better in Ireland but is different than what we have here. The list goes on.