Gotta make her feel bad about it as a person.
Watch it with her and constantly put down the show, the people on it, what the people on the show are doing, and "the people" who watch those shows. Gotta be somewhat subtle. It may take a month or so, but eventually it will stick.
Gotta do this right. Any other way will only provide temporary results.
Ingrain it in her mind that those shows are horrible, or some bs. That way, when other shows similar to that come out, she will relate them to these shows and not want to watch the new ones either.
If done right, it kinda turns out like a Pavlovian(sp) thing.