Because there is no way you will buy goods as a business man and not expect profit so gambling should be seen as something that will be beneficial to the gambler financially as it's more like an investment
You might have a different point of view, but that is not how you actually should treat gambling. Once you start gambling, thinking it's a way of making money, you will end up being broke. There is a saying: house always wins. You cannot really beat the house in the long run. You may win something in a short session, and maybe you will be in profit. But if you plan to play more and make money, you will lose everything.
People spend money on entertainment. Don't you subscribe to Netflix? Don't you go to amusement parks to entertain yourself? Don't you go to the bars to entertain yourself? Doesn't that cost money? You cannot expect a return from everywhere. You get entertainment in return.