Honestly, I don't buy the fact Muppet stuff wouldn't sell either. The Vynalmations are always going, The Muppet Pookalooz were selling better than the other ones (those and NBC), T-shirts seem to go alright.
I have no doubt that a couple plush toys at least would do pretty well... I still think they should have slowly introduced Kermit, Animal, Piggy... and then when the movie arrived, Beaker, Pepe, Walter...
Up probably has to do with Ratatouille stuff not selling. I WISH I grabbed a bunch of that Rat stuff... all I got are 2 lollipop toppers and a plush of the dead chef. Still, there was NO excuse to not mass produce and sell the figure set.
ANG stuff never really happened because, after all the crap that went down with that movie, they pretended it didn't exist. I'm disappointed they didn't have anything for Emperor's New School or the movie's 10th anniversary.
BUT... with the rerelease Lion King merchandise, they had large plush of the background in the opening number animals... so maybe we'll see something great when the movie finally comes out.