Suppose a real gambler will budget a small part of his monthly income, especially only 1-2% of his monthly income, for gambling. And when he runs out of this budget, he will never refill it, only refill it again at the end of the month, in which case he will not participate in gambling when his budget runs out.
I agree that the real gambler won't spend too much money in gambling. Spending 1%-2% of the monthly income is enough, there is no need to have higher amount of money. We mostly gamble for fun, it isn't a proper place for earning money. So when the gambling budget has been over, it is time to stop the gambling games immediately.
But an uncontrolled greedy gambler will spend almost 15 to 30% of his monthly income on gambling. When the budget is exhausted, he will participate in gambling by taking out loans or borrowing money at high interest rates. In this case, instead of controlling himself, when the budget is exhausted, he will participate in gambling by managing his money in any way.
Well, spending more than 15% is too much. Sure, we can call they are uncontrolled gamblers if they spend 15% - 30% of monthly income for playing gambling games only. And when they decide to take a loan or borrow money, it is very careless way in gambling. This possibly leads to the problem in the future because we probably can't recover losses. Instead of earning higher amount of money, we only waste more money.