Because this is a free country. Because religion (or not) is usually inherited, and not chosen. Problem Child does not have Christmas shows. Yes, maybe one or two Christmas tunes.
This is to show respect to all the non-Christians in the USA, and the whole wide world, listening on the World Wide Web.
Be you a Jew, Hindu, Muslim, Pagan or Other- Happy Solstice and Seasons Greetings to all!