You have a point, once you accept reality then you wouldn't have a problem with losing . The reality of gambling is that it's a game of wins and losses, its possible to lose and also to win at some point. This is the reason why it's important not to take it too seriously because you already know that the outcomes can be random. Those that cannot accept defeat would always chase their losses.
True, unfortunately, many people when they start gambling are aware that they should play just for fun, but the problem arises when they start losing. They can't accept defeats very gracefully, even if they have invested small amounts of money, something that even if they lose, they won't miss in the real world.
Even so, people lose their temper, become violent, continue gambling thinking of revenge on the casino, and when the losses don't end, they destroy things in the casino. Few people can handle defeats well. That's why I always advise people not to get involved in gambling when they know they can't handle losses.