More than 50% of the world population gamble in one sport or the other and some are making good money while some are still hoping and praying for their luck to shine.
Gambling is a source of income for the gambling industry. For gamblers, the source of income is mainly their wages from their place of work. Of course, there are exceptions; few gamblers can win big, but these are exceptions, not a mass phenomenon. If it were otherwise, the entire gambling industry would have gone bankrupt long ago.