The behavior is reprehensible, of course. Sadly, you will find that it is very typical for artists to feel like they've been treated as disposable, especially in the animation industry. But, in the long run, they will probably be better off without their name on the film.
The movie looks like it is probably terrible and I suspect a viewer would walk away having gained nothing substantial. I am likely among the most guilty of people I know for finding puerile things funny, but I've heard people talking about this movie like an approaching legend or wistfully hoping it will break the "curse" of western animation being relegated to works for children.
If this is the west's ideal for mature animation, then may the Disney bane remain upon us forever.
I can just see the ironic sneering of a writer with indignant condecension at the thought of a Frozen sequel while they write their fiftieth weiner pun.