I think it is rather obvious. One movie was creative and well done beyond all others. Yes, Chicken Run was Best Picture for 2000.
Oh yeah, I forgot, the Academy Awards have become a promotional vehicle with over half of the votes coming from people who don't even make movies.
Well, then, since you can't be an agent for a clay chicken, then the best movie from last year that had people in it had to be Best In Show. Oh yeah, not enough promotional possibility. Shucks.
Hell, might as well give the award to a Steve Reeves sword and sandal flick. Gladiator wins while I check out the public vomiting stalls.