That's kind of surprising. Academy members are not required to watch all the nominees for Best Animated Feature before voting. In fact they are not require to watch any of them. Several years ago I remember that after a year where the movie that won best animated was not the one that those in the animation industry overwhelming thought was sure to win some animation industry magazine survived Academy members asking w…
The Academy has a reputation for seeking "artistic merit" even at a cost of good entertainment. They're hoping to advance something that didn't do well at the box office. Sometimes that means giving awards to films that turn out to be dogs, but sometimes they manage to promote things that deserve attention.
A lot of Oscar-bait gets a small release at the end of the year, to qualify it for the Oscars. If it gets a nomination, they'll use that as part of a wider campaign later. That's why they send out screeners: they know that many members won't have had a chance to see it in the theater.