Actually, according to the Wizard of Odds page I linked to above, the Vegas Hilton has 2-deck surrender blackjack which is literally scratch odds assuming you use the perfect basic strategy for those rules. Factoring in free drinks, you'll come out ahead in the very long run. Of course it's probably one table that's open a half hour a day or something.

But your rule holds for 99.9% of the tables, and the casinos know only a small minority of people will play *perfect* basic strategy given the many different rule variations.