Dealer checking for 10 or Ace

I recently had the opportunity to visit Reno for the first time. I noticed something that I never saw at other casinos. Their 10�s and A�s on the Blackjack tables have black lines on them that are apparently used by the electronic scanner that checks for a 10 or an Ace. (This is different than type of system in some Vegas casinos that has the scanner with the A and T buttons)

Why does Reno use this technology?

Is anyone else using this? (With the exception of a few Vegas casinos that use a push button system to check for the 10/A in Vegas I never seen anything but standard window with mirrors.