Is it just about perfection?

A question to those clambering for Bud Selig to reverse the call and award Galarraga a perfect game: Is it just about the perfect game, that unique historical rarity? What if it had been an ordinary no-hitter? A one-hitter? What about a shut-out (where the outcome was otherwise unaffected)?

I am trying to figure out why this would not have the commissioner reviewing all sorts of calls post hoc (although Mitch Berman's suggestion could limit this problem). I just am not exorcised about the "correctness" issue, at least where sports are concerned. I prefer finality and redoing all sorts of things once the game ends.