I would think that the cage would have the same electronics as the tables do to verify the value of a stack of chips you're cashing in.

An interesting question though is what would actually happen if you tried to play a disabled chip on the tables. The electronics I assume would just not see it. Yet you visibly put it in play and presumably the casino accepted it. Seems to me, they would have to pay off on the bet, but maybe would confiscate the chip after the dealers count and the payoff-display didn't agree. This could be prevented if the table contained a sensor to tell how many chips were physically in play (weight, or ultrasonic sensor for height of the stack); this would be pretty hard to implement reliably though.

As an engineer who had to design real-world systems that worked reliably, I'm dubious that there will EVER be a practical system to verify bets and determine winning payouts. I would guess there would be chip-less play long before that happens... ala TITO on the slots. Load your playing position with bills or casino credit, key in your bets with a keypad of some sort, and accumulate credit that can be played or cashed out in paper form. This would not be hard to do, but the cost of the tables to implement it would be considerably more than the current wood and felt tables the casinos use.