Well keep in mind the animation does take a very long time and the more minutes you can shave off and just get to the meat of the story, the happier the animators will be! Besides, that's the beauty of animation, you can do a lot with little, since you don't have to worry about space limitations or sets, or weather or union rules or whatever. The scene can take as long as it needs, but not a second longer because you're going for impact.
Live action you can sort of lollygag for a while, animation you don't have to. I mean, an hour is pretty short, especially when you're paying maybe $15 bucks for that hour, buuuuut they had damn well better include things like a behind the scenes, deleted/alternate scenes, concepts, promos for future movies - since those are almost better than the movie LOL AND a commentary track. If you're going to have a short movie, then dammit include a commentary track, at least it makes it feel like a 2 hour movie since you can watch it twice.