There is actually no such thing as a legal gambling activity (on and offline) for residents of and visitors to Qatar. The laws are strict and are enforced, and online activity is closely monitored. Authorities have gone as far as to block offshore, and foreign operated gambling platforms.
Despite the illegality, camel race betting is both accessible and extremely lucrative for those in Qatar. People can win anything from small change to seven-figure payouts. The sport and betting on it, are very controversial, as there are children used as jockeys, many unfairly treated and too young to be legally able to work.