Great question — answering as the UphillTech team:
I can answer this for the "usual" case. People do all sorts of weird things in sports wagering and the ilk; but the 95% case is here. The eight teams you reference are the First Four . They are the "play-in" games; the winner of them feeds into a couple of spots on the main bracket, either as 16 seeds (2 of the 4 games) or as 11/12 seeds (2 of the 4). Most brackets do not require you to fill them out (although you certainly could set up a tournament that required it); I assume largely because they mess up the nice scoring method of 1 point for 1st "real" round -> 32 for "finals" all being powers of 2 and all giving the same value for a 100% correct round (32 each round are available). Once...
Full answer by Joe: https://sports.stackexchange.com/a/8950 (CC BY-SA 3.0).
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