Does anyone seriously purchase games below an 80 on Metacritic though?
Only if I seriously investigate (or as am invested in the Lightning saga as I am) and see what is the dividing line. After all, a lot of masterpieces didn't get good reviews from the start. Suikoden II got good/mediocre reviews when it first came out and is now seen as a masterpiece. But for the most part, I do take it as gospel.