People can make bets not only because they want to support their team, but also if they want to earn some money by betting on teams that have real chances to win matches. Some people even learn latest match results and different teams to make a right bet.
That's for sure, it's not so hard to predict result of matches especially if you are good at that kind of sport, so betting can be a good way to earn money.
Or you can invest in projects such as this and make a living out of passive income. Of course, if you have a knack for betting and you're actively researching which team performs how good, might as well go for both.