Because CS has always been attached to a primary TV market of Waco and the Fox folks up there don't object when they have a chance when the initial plan comes out. More people need to complain to the station manager.
But it would also help is the 3-4 guys at Fox HQ would realize BCS is closer to Houston than Dallas and assign Texans to Waco when they aren't against a Cowboys game. Likely, there data considers the Waco market as being more interested in watching one of the Cowboys' rivals than an instate team. Sucks being the appendix to Waco
Just read a great article on the complexities of the process.
https://mobile.nytimes.com/2017/11/19/sports/football/why-people-in-mississippi-have-to-watch-the-giants.html