First time I was in Vegas, I had spent the previous week memorizing a book on black jack strategy and card counting. My dad took the easy route and just xeroxed the cheat sheet out of it. Anyway, we sit down at a table at a major casino on the strip and my dad asks if he can use his cheat sheet. The dealer looks it over and says, "Sure, stick to this and you'll be fine." After a very short time, I was down about $15 and my dad even more. My dad wanted to keep playing and win some money back so I cashed out and stood back to watch the play. After a few more hands I put together what was going on. I leaned over and whispered, "this deck is missing face cards." My dad realizes we're being cheated and nearly knocks his chair over getting out of it as fast as possible and leaves the casino. At that point the dealer is looking at me and the pit boss is looking over, so I figure I'll be asked to leave anyway, inform the dealer that I think they're cheating and leave.
About a day later we're riding a bus and talking to the driver about what casinos to go to and my dad mentions the black jack incident and the bus driver says, "Oh, didn't you see the sign that said Spanish Blackjack. You don't want to play those tables because they remove all the 10s."
Moral of this story is that its very easy for a casino to cheat you. The dealer knew full well that my dad would have to adapter his play because of the missing cards, but told him to follow his cheat sheet and never mentioned we were playing Spanish Blackjack.