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There were a lot of actors who were not credited in MTV's film Orange County. Most were young, playing students or other kids.
However, two uncredited actors stand out: Kevin Kline (author Marcus Skinner, the protagonist's literary hero) and Ben Stiller (the fireman). Both had lengthy dialogue in one or two scenes.
Lily Tomlin and Chevy Chase both appeared about the same amount as the above two uncredited actors, yet were given a credit.
Why were so many actors, in particular Kevin Kline and Ben Stiller not credited?