I used to count cards at blackjack. And when I did it in Reno, at a certain stage a new dealer would be brought to the table (outside the normal shift schedule). And from that point on, I would lose money. If I watched closely, I could see them dealing seconds.

This seems like quite an irrational strategy on the casino's part, and a bad case of loss aversion.

Suppose the casino calculates that it can afford to cheat one customer in twenty without getting caught (or any other proportion if 1/20 is unrealistic). Of all the people they could use this ability on, is the card-counter really the optimal choice? He may not have come in with very much money, and is likely to catch on reasonably fast at which point he will probably just leave. It seems much better to wait for someone who is at least slightly drunk and has come in with a lot of money to gamble, he probably won't notice and will just keep making and losing large bets. If I recall correctly the margins in card-counting are quite small and they may be able to take many times as much money from the second guy as the card-counter can take from them.

Although you obviously have much more experience in this area than me, so please correct me if I'm wrong.