This is my guess too, either the service dealer council said no way, the chev warranty dept looked at the hours they would burn up doing a fix or the expertise at the dealer and factory was too steep a curve, probably all of them....Realistically there was no way to do this at the factory. It would slow down the production process greatly as it takes experienced installers hours to apply film. Then if there were issues (which can happen and do) how would GM back the warranty on the install without having installers all over the country???