Commodities are routinely compared worldwide, and peanuts could be considered commodities. They are certainly closer to commodities than to services etc., even when packaged for the individual customer in fancy wrapping.
I would understand your argument if you were talking about services.
The US produces the 5th most peanuts of all the countries in the world (interestingly, Sudan makes more). It may be a commodity but it’s a local one that doesn’t have to be internationally shipped or be taxed via tariffs. Also, in the US we don’t have VAT and apply sales tax post-hoc, so comparing store prices is really skewed by that.
"doesn’t have to be internationally shipped or be taxed via tariffs"
I agree with the taxation (duties), but actual shipping overseas is dirt cheap. It is more expensive to move your cargo overland by a truck than to move it to the other side of the world using a cargo ship.
The cost difference between moving a container of peanuts from Alabama to San Francisco and moving it from Alabama to Sydney is surprisingly small.
I don't think that point stands for peanuts. I can get a 500g bag of peanuts right now for 2.7 Euros and most likely the reason for that is the cost of living around here.
I would understand your argument if you were talking about services.