The realization that we need to be financially responsible is a very good reason not to gamble foolishly, no responsible person should use significant amount to gamble because it's not a business. If you realize that winning in gambling is by luck and beyond luck there's the house edge, you wouldn't put all your hope in winning. If you know that you can be addicted to gambling if you devote more time, money and energy into it that it can ruin your life, you will learn responsible gambling. Every gambler have enough reasons why they shouldn't gamble foolishly because anyhow you look at it it won't end well for the gambler. Responsible gambling is key to mental health of every gambler.
For me, simple calculation also matters, if I treat gambling as entertainment, I will never spend large amounts of money on it. If I see that another investment can bring me significantly more profit for example, buying and holding bitcoin, then I’ll do that. I’ll direct all my main funds into investments because that will bring me more money. And since I’m not a particularly strong gambler, but I enjoy playing, I’ll do it with small amounts that I’m not afraid to lose. And if I win something, I’ll use that profit to buy bitcoin as well.