The casinos are not manipulating anything, you are just lucky. I used to think that every beginner had some sort of luck but that's not actually the case, if an Intermediate player had bet on that same game the gambler would have also won, the casinos don't really look out for beginners to lure into gambling, that's just what we have been made me believe according to our previous experiences. Luck is just a matter of hitting the right timing
I believe the reason why beginners often get pretty lucky, making it look like the casinos are actually manipulating this whole thing is because the beginners, since they’re still pretty much naive, it becomes a lot more easy for them to actually control their emotions, set realistic expectations and avoid being greedy or overly reliant on their skills. As we already know that if a gambler manages to have all of these, then he’ll most likely have a much higher chance of making better gambling choices and of course increase their success rate too. I think that’s just what happens there