It is not surprising since we can see how easy gambling access is in America and it makes more people gamble than investing because it is easier and faster for them to access. It also offers a chance for someone to change their life overnight, even when the chances are small and the results are much faster, compared to hoping for investment in stocks. Things like that are strong reasons why many people put their hopes in betting on sports in order to get rewards that they can use to meet their needs or other things in the midst of a difficult economy.
Another added factor is that most people don't understand the stock market as much as they can easily learn about gambling. Gambling too, they can use as little as what ever amount they can afford to place their bet compared to the stock market, where they need an exact fixed amount before they can afford to purchase a share, and gambling also gives them the advantage of multiplying what they put inside in little time, not like stock, where they need to wait for stock value to increase before they can start making profit.