Dealer cheats and casino cheats, not the same thing
First off: Probably 99% of claims by people that they were cheated in a casino are probably just sour grapes after a big loss. I have both an operations manager and a table game manager in my family and though we kind of stay away from the subject of gaming, the subject of complaint letters has come up. They get tons of letters (most phone calls are diverted to someone who screens the calls) and most of them do not have any merit, in their opinions.
Since most people lose and also play very poorly while thinking they play well, it does not surprise me that facts are not important when angry folks express their frustration at casino management.
So I believe that casinos are honest and dealers are honest, but their have been exceptions.
Dealers cheating you to make up for an earlier time where they cheated the casino is a thing that does happen but it is rare, as is the dealer who has the ability to deal seconds. In this case, the casino did not cheat you, the dealer cheated both you and the casino and the casino actually is more interested in getting this guy.
Casino cheating is also rare. The short shoe, take some aces and faces out and add a couple of extra 5's and 6's, is perhaps the easiest way to do this and the simple way to show your customers that you do not do this is to spread the cards when the decks are changed. I know a casino that does not spread the cards but I believe they do not cheat. I base this on my have counting down enough shoes there to feel that you do not get more positive counts than you should get. I feel they do not spread the cards for the reason that they are greedy and do not want their tables not generating profits while cards are spread. This is stupid on their part, because a percentage of players will think they just might be cheating. Trust is a key asset for any casino.
I know that short shoes have been discovered in Eastern Europe, mainly in the Czech Republic. One California Indian casino was caught about 7 or so years ago. I believe a midwest casino was recently caught, but do not remember where I read that.
In this country I do not worry about a casino having a prism shoe (a few blackjack books have phots of them for ID). It is also doubtful that if a casino decided to cheat, that the dealers would be in on it or know it. Dealers move around, dealers will talk to friends and family, dealers could just not be really trusted enough to be informed and also would require quite a bit of extra compensation to do this. This is another reason not to worry much about a prism shoe, as I do not believe the dealer will be bringing his own shoe to the game.
Casinos do worry about dealer cheats. The dealer can steal more from the casino than he can from the players. Look at it this way, if he steals from you, it goes into the rack. If he steals from the casino, it finds its way into his pocket. If a dealer is cheating a customer, the first thing the casino will think is that he must also be cheating us. Not for any real love of the customer, but because of similar interests, both you and the casino are most likely allies in this situation.
ihate17