I did a CM blog search for "Kardashians" a few minutes ago and two blogs came up, neither of which was complementary to the show or to the actions of one or more of the gals on the show.
Kids watch a lot of stuff that isn't fit for human consumption on TV these days, and some parents will monitor that and some won't. It's your opportunity as a teacher, if it comes up in your classroom, to tell them how you feel about it. I think teachers are huge influences in childrens' lives. If given the opportunity, voice your opinion about how that kind of conduct affects society overall. I personally have not seen what you are describing as a CM approval of the morals advanced (or not advanced) on either show.