Gamabunta and the other huge frogs were summon right in the middle of Konoha...Was that because it was destroyed or would they have ended up there regardless killing some people and destroying buildings?
Even if Naruto does beat Pein..Pein used a jutsu that uses up a lot of energy, and it's still only puppets witht he most powerful one unable to do his jutsu. Pein has been using a lot of jutsu even before the huge shinrei tensei or whatever it is also. So Naruto winning would still be PIS from the fact Pein isn't at full power.