Let's first talk about how the poor gives the money to the wealthy.... They allocate a huge part of their money (which isn't a lot in the first place) to gambling thinking that this would be the quick fix to their problems. This is how they give the money to the wealthy in this case the casino owners.
But the money can also go from the wealthy to the poor. If the tax from casinos gets collected by the government and is used effectively, it can help a lot of those in need. The money can be used to improve infrastructure, education, healthcare and etc.
This is not still perfect as the money collected for tax and to be used to develop the country for infrastructural development, health care and other sectors will still be benefited by still the rich and the poor in the country. The rich might even get to benefit more from it more than the poor due to their influence in one way or the other. So ultimately, the casino only benefits the rich more because they get richer by the day through losses from players playing in the casino which most of them end up losing in most of their bets.
Naturally, a poor person can start up a casino, so it means that a rich person is just using this means to exploit and get richer again and the adverse of it affects the poor more who thinks they can win a jackpot and fetch from the riches of the wealthy ones which in most circumstances don’t turn out to be so.