“Casinos do not use the same kind of dice that come in Yahtzee! or backgammon sets. They use what’s called Precision Dice.
Gaming dice are cheaply made and importantly, they are not random. Gaming dice have rounded edges and pips. The little dots cut out from each side to form its numerical value. This produces an uneven balance as the “six” side has more pips (less material/weight) than the “one” side. Because of this, pips and rounded edges can skew the randomness pretty heavily.
Only precision dice, used correctly, are truly random.”
You don’t need snake eyes to read the whole article, at boingboing.net.