Only idiots bet on casino games. I'm a winning bettor but struggling to bet because limited on almost every book.
I believe you have a point, casino games are not wired for the best of the gamblers, the algorithm in it is to favour the house, so there is no way many people try, though some would win, but the house will always win more. Those who are lucky can win big with casinos though, which is why I believe they are trying their luck all the time to play it over and over again, and who knows if they can actually win big. Casinos scare me to deposit big into my account and start playing due to this, but for the fun, I think the casino has the entertainment most as you can switch games and have fun.
It now depends on the reason why you are betting as you can actually plan your low-cost fun with it, and by having good plans alongside it, you will not even feel it if you lose money. Those who feel it are the ones that deposit big money into it which I do not often advise unless it is a sportsbook we are talking about just like you hinted as well.