I am pretty sure that even if a person with a financial status of spending 20 dollars a month or week, they will still play and bet higher than that if they win consecutively. That is how gambling works, you have money, you play in order to make the most out of it. So, it is impossible to just waste that exact certain amount.
It's not impossible with discipline, let's say you are gambling with a fix bankroll of $100 and you'll stop right away once you lose everything, then that is a real discipline, I know some people can do that but us who can't maybe say its impossible.
Sometimes, if we are winning too much and still continue to gamble, all of our funds could be lost, there are instances that it pushes us to borrow money and in that way I can consider gambling as a threat. Mainly, fun with the experience at the start, but a threat to consider in the end.
This is already out of your plan, when you set up a bankroll you start gambling and you think of stopping when you lose, but when you borrow money after such effect then that tells you'll be at a higher risk as a gambler.