Why isn't this the other way around? What am I missing?
1st and 2nd round games. the committee likes keeping those upper seeds close to home. Lexington, KY is reasonably close to OSU and New Orleans is about as close as you'll get to Florida. i guess they felt the first 2 rounds were more important to have closer to home than the 3rd and forth (and rightfully so).
But the 1st and 2nd round sites can host any bracket. For instance Chicago is hosting Kansas (West) and Wisconsin (Midwest).