It is unfortunately not very common to create an anime version of a popular TV show, but I think that this practice should be reversed. Anime adaptations help bring a new audience to a television show that would otherwise not be interested. This brings in more money to both the original show and the adaptation.
For some reason we feel the need to re-hash the re-hash. If something is good it does not necessarily need several incarnations. Sometimes it is best to leave things alone. I am not big on anime so I do not really see the appeal in making television shows into anime.
Anime is very popular but it doesn't mean we should start automatically making more television shows in to an anime adaptation. Each individual television program should be looked at, and possible demand gauged, to then decide whether it is worth creating an anime version. If that results in more anime version being created then fine, if not that's fine too.
Of course there is an audience for anime, but it is not necessary for more television shows to get such an adaptation. There are already plenty of anime shows out there so it is not necessary to adapt current shows for that specific audience when they already have a loyal audience.