That is why some sites offer rewards to those who can find bugs in the system. Though it was their part to investigate and look for some irregularities inside but as responsible gamblers, we also have to report even though we never get money because there is trust which is most important. As long as the site has not cheated anyone, they should also get respect and no reason to cheat. Cheaters could be found too easily, so we never have to try it because in the end, we are the only ones that suffer the most.
Besides that, there's no point in cheating the casino. After all, the casino will know if we are cheating on the casino because the casino can easily check all of its user accounts. And after being caught, the casino can punish us according to the rules that apply at the casino. If the casino wants, our account, including all our balances, can be blocked easily to make us regret what we have done. It's better to report to the casino if we find a bug so that the casino can immediately check and fix it. After all, the casino could have rewarded us for helping the securities team find the bug.