I've thought the same thing. I was in a waiting room not to long ago when I asked about changing the channel from CNN to Fox. The assistant looked puzzled.
I told her, "Please either change it to Fox News or to the Cartoon Network. Spongebob Squarepants is more informative than CNN."
I think the airport has a deal with cnn. A hometown thing I guess. The only tv’s in the whole airport that aren’t on cnn are the ones in sports bars.