Why Isn't Every Texas Rangers Preseason Game on TV?

Does Fox Sports Southwest have better programming during the day?  If the answer is no, then why are they (or some other local DFW channel) not broadcasting each Rangers Cactus League ballgame?  In the year two thousand and thirteen (2013) why can I not turn on the television and watch each and every Rangers preseason game?

For example, Martin Perez (the would-be 5th starting pitcher) broke his arm yesterday when when a liner hit him when he was on the mound.  But no one I know around DFW got to see the game today because, IT WAS NOT ON TV.  That of course is bad news for the Rangers but I'd like to see bad along with the good, just like I do during the regular season.