Why Sport Books:

Sports betting customers are more loyal than casino players once they find a sportsbook with odds that they feel are fair. They are generally committed for each season of the sport that they are following, and often they wager on multiple sports. Football is currently the most profitable season, but even when football is not played, tennis, horse racing, the NBA, and various other sports keep bettors betting.

According to Merill Lynch sports betting will account for 55% of all internet gambling. This is a huge piece of the gambling industry, and it is far easier to rank well in search engines for sport related keywords than with poker or casinos. 

Even webmasters who know nothing about sports betting can earn good money. The programs listed on this website provide live feeds with odds from different sporting events. 

This is a huge gold mine that has for the most part been ignored by affiliates.