Is player analysis software cheating

I have been an advantage blackjack player in Las Vegas for over 15 years now.  I have played in almost every good game in town over those years.  I know that it is illegal for a player to use any device that would help them count and beat the casinos.  So why isn't it illegal for the casinos to use software that analyses how well someone plays?  Why isn't this considered cheating by the casinos?  Doesn't this give them an unfair advantage over the blackjack player?  Why should they be able to use this type of software to limit play by anyone that could possibly beat the games they offer?  They already have full control of the rules for each table.  Are they really that scared of AD players?  Why not just change the table rules instead of spending so much time and money into finding AD players.  It seems to me that they should not be allowed to use a computer to figure out how well others play. They should have the same limits as the players.  If they want to find AD players then they should be forced to train their personnel to spot AD players on their own.