If you can come to such a conclusion, you know what to do with gambling. Gambling is just a tool to help us enjoy our free time and not to be used as passive income because it is very difficult to do unless you can own your own casino. Gambling can indeed provide income, especially for those who can win many times but please remember that those who often win will also experience defeat. For that, it is better to use gambling as a way to enjoy our time and nothing more.
some people always think that - when you will start gambling -you will only win and gain profits and money.
but you are right - its not always a win - there are losses as well. And that's not a reliable passive income. One should look for another opportunities for the passive income.