Hitting the Wall

So I was watching Wall-E the other day for the Nth time (where N=N+1, which explains how many times my kiddos want to see this particular movie) and I noticed something that bothered me and now I can’t get it out of my head.  When Wall-E is hanging on to the outside of the rocket ship there is a shot of what I’m assuming is the Milky Way (or a similar shaped galaxy) which make me ask “how far away did they have to take the Axiom to escape the pollution of Earth?”  The answer, apparently, is a long, long way.  I asked Isabel for an explanation, but she started yelling “today is Wall-E’s birthday” over and over.  And if they can travel past billion of stars, why couldn’t they find a new planet on which to live?  Also, how much of the pollution on Earth was a direct result of building hundred of thousands of space ships and launching 10 billion people across the galaxy?  Think about it, but try not to let it keep you up all night.