1. lots of kids and hipsters see this movie and decide they need a fixie.
2. bike shops make a lot of money selling fixies for the next year, then get stuck with the extra stock when it dies down.
3. parents and pundits complain about wreckless youth bombing through traffic without brakes. a few kids get hurt or die.
4. fixie trend dies.

this happened once before. BMX died in the early 90s because of over exposure. remember this?