If you bet on 0 or 00 on an American wheel, and your bet hits, you'll get a payout of 35 to 1. If you place a "row" bet (betting on both 0 and 00), and your bet hits, you'll get a payout of 17 to 1.
The 0 (single zero) and the 00 (double zero) are the green slots on the roulette wheel. These pockets could receive a 35:1 payout if hit straight up. If there's a split, the payout could be 17:1. This type of bet is somewhat risky, but the payouts could be worth it.
The amount of money a bookie can make depends on many factors, such as; the number of players per week, how much per bet, and how often players place bets. The more money involved, players, and bets that are made per day equal more money for the sportsbook agent.