Tarantino has a thing for not showing the main event that triggers the whole movie. In Pulp Fiction, the whole second half of the movie is centered around how Bruce Willis killed a guy in a boxing match. You see everything before and after it, but you don't see the match. In Reservoir Dogs, the movie is all about a big jewelry store heist, but you never see the heist. So it figures that the biggest event for Kill Bill, the asswhooping of the Bride, wouldn't be shown.