The people who left Earth, the ones who were responsible for the condition of the planet, were all very thin and active. It was 700 years of living in microgravity, being waited on hand and foot by robots who wanted to protect them from harm, that led to the obesity. The movie was pretty clear about this fact, down to the portraits of the captains of the vessel, who started out very thin, then gradually grew larger as generations passed. The fat people were not to blame for the dystopia of Earth, they were fat because they lived in a microgravity world where their safety was ensured by robots that wanted to protect them from harm. Actually, the characters portrayed were more than happy to interact with the larger world once they had the opportunity. Wall-E was a great movie, a classic. There was no fat-hatred protrayed, or any other kind of bias. In fact, it showed the people as being pretty darned noble, all things considered.

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