Hate to be the skeptic, but what's to guarantee that the winner will distribute the winnings evenly? It's not like the site has any official connection to the contest.
Hey, I'm one of the guys working on this project. You're right, we're not sure how to make sure the winner splits the money with everybody, but given how unlikely it is that anyone wins at all, we're just focusing on executing the bracket distribution for now. If someone actually wins, figuring out how to get that person to split up the money is kind of a nice problem to have! Just think of the drama...!
This is exactly what I was thinking. What's to stop someone from pulling a "Oh, hey, thanks for the winning lotto ticket..."
If the answer is "personal integrity and honor" then, well, call me a skeptic - but some people may just come up a little short after a billion-dollar soul searching.