Here's an overview of using options as a technique to take advantage of unique situations in the futures markets. Insurance companies are consistently profitable because they use the laws of mathematics, probability and special circumstances to their advantage. They can pick and choose who they want to insure and the prices they want to charge for insurance.
Casinos use comparable principles by which to profit.
When you gamble on roulette, you appear to be given fair odds on your bet. There are 36 numbers in the roulette wheel and if you pick the right one, you are paid off at 36 to 1. This is the casino's edge, game after game, day after day. Professional bookmakers enjoy related mathematical advantages. If a bookie takes bets on a prize fight and balances his book properly, half the bettors will win, and half will lose.