You're asking irrelevant questions. Your claim was that Metacritic is an "American" (because English=American) website (internet geography 101. Get those cyber Mexicans out of our borders!!!), and therefore shouldn't include "foreign" (I have no idea why you used quotation marks) reviews.
The site includes reviews from all countries, because it wants to give a representation of the overall critical reception of the work. It's not trying to be a critic itself, or push an "American" opinion. It's meta-critic. It's just trying to record what ALL the opinions are, not just American.