With learning self-control, a gambler will not trying to break his control and limitations because he knows that can impacts to his finance. He will not spend too much money just playing gambling as he doesn't want to see many losses because he only want to having fun by playing gambling. He will hold himself by his limitations to prevents the losses and anticipating the risk becomes bigger. He will thinks to use his money to fill needs first and will allocate some money for gambling so he doesn't use much money for playing gambling. He will always try to prevent himself from changing his behavior before and after playing gambling because he knows that playing gambling doesn't have to be too serious.

Agree with what you have said and of course all of that will be part of the gambler being able to be in comfortable or safe condition from some of the bad influences of gambling, but I would say that gamblers are not able to apply all of that.
There will be times when under certain conditions gamblers are willing to spend larger amounts of money which of course is an unacceptable amount, they will do so when they really have different view of the opportunities that are present.
I have many gambler friends and I myself gambler, we have limits set aside for our gambling allocation each week but sometimes we go beyond all limits and bet larger amounts.
Only difference is that no matter what happens there is no regret that drags on too long and assumes that what happened will disappear because everything cannot be returned and it will only be an attempt at something stupid if it continues to be regretted as the desire to restore it arises.
This is change in the behavior and attitude of gambler, even though he is wise and responsible gambler, humans have an attitude that easily makes mistakes and no gambler is immune from the mistakes they make.