It isn't like Hollywood changed "The Lorax" story all that much in order to indict capitalism or Republicans or materialism or whatever all Hollywood movies have to address in an election year.  Dr. Seuss went after racism and every other topic and both the left and the right assumed he was on their side. He was that clever.  The movie, not so much.

In the film, Thneed-ville is a plastic wonderland without a single leaf but if Ted wants to woo Audrey, he needs to show her a real tree. Enter the Once-ler, who tells them the story of how Big Business was not micromanaged by progressives and killed all the plants. No problem in the subtle hands of Seuss.  Done by heavy-handed movie moguls who think they need to dumb things down for the audience, it is basically "Fern Gully" with better graphics.

Christian Toto writes in his review
The Lorax would cause a commotion thanks to his bristly mustache alone. But DeVito makes his oddly urgent proclamations – “I speak for the trees” – the kind of battle cry modern tree huggers will call their own. He’s angry, not joyous, with an edge to his voice that would make him a fine candidate for an eco-terrorist academy.
Adam Mazmanian of the Washington Times is much harder on the film than conservative Andrew Breitbart's Big Hollywood site, writing "“The Lorax,” the animated 3-D feature based on the Dr. Seuss book, is a movie the Unabomber would have loved" and then
“The Lorax” is relentless in propagandizing how the use of natural resources to create consumer products is inevitably catastrophic. There even is a song in which the Once-Ler defends his practices by invoking social Darwinism.
No surprise there. 2012 is apparently the year of the return of progressive justification of both social Darwinism and eugenics.  There will even be a whole book talking about how Republican brains are physically flawed and progressive elites need to understand that in order to fix the problem. It should be fun.  "The Lorax" movie, apparently not.  Unless you write for Greenpeace.