I knew a guy who was absolutely terrible at money management, he bought Ether with money he had saved for vacations. He ate poorly and didn't buy clothes to make this investment, after which cryptocurrencies fell in price. This example is also great for betting and gambling, I think everyone knows guys who bet with their salary and then complain that prices in stores have risen so much that it is impossible to live normally. You need to take care of yourself in the future, because we will all end up there. You need to be able to save money, or bet only with extra funds.
This will definitely be a problem for him, not only in gambling but in real life. When he has to face dark times with little earnings and a lot of expenses, how will he do if he doesn't know how to manage money properly? He will get into debt and this will lead him to a self-destructive spiral.