You are generalizing way too much, it is true that casinos will give themselves an advantage on each and every game they make available to their customers, and it is also true that some of those customers could become addicted to gambling, but they are a minority, not only that this plays against casinos, I have always thought that casinos do not like that people get addicted either as not only this generates bad publicity against them and high regulations but it also reduces their profits, as it is obvious that a casino will obtain way more profits by having a lot of clients which lose a little bit of money than by having a small poll of clients of which all of them are addicted.