Questions like these could do with a country tag (see the comment answer).
I tried to edit one in, only to find out that there seem to be no country tags....
I'd be more inclined to just mention it in the question when it's relevant. Tagging is more a searching/organization thing than a way to convey important information about the question. You don't see the tags until you're done reading the question, and even then a lot of people skim over them, so tagging something united-states will only help so much.
Imagine you wrote a question "How do I make my pie less juicy?" (plus a suitable body) and never said what kind of pie it was until adding a blueberries at the end. Seems kind of unclear, right? I think the same applies here.
I can't imagine a country tag would be useful for very many questions. Your example might be one - terminology that's specific to one country - but even for that one, I don't think it would make sense to hang a "US" tag on it: there's lot's of cross-border shopping between the US and Canada, so sweet cream butter shows up here as well, but then does that mean it needs two country tags?