In this context, the "medium" is the country where KFC/McD is situated, and the "message" is the set of food standards or "the bar" as we're calling it in this discussion.
America truly has bad food standards in general, so the KFC/McD in America reflects that reality. In contrast, Italy has a much higher bar for what is considered food, and KFC/McD reflects that as well.
In this context, the "medium" is the country where KFC/McD is situated, and the "message" is the set of food standards or "the bar" as we're calling it in this discussion.
America truly has bad food standards in general, so the KFC/McD in America reflects that reality. In contrast, Italy has a much higher bar for what is considered food, and KFC/McD reflects that as well.