Being an irresponsible gambler is not by maturity it is by experience. One is likely to become an irresponsible gambler if they just started gambling than one who has already being gambling for a long time and has seen the ins and outs of it.
Secondly, people respond to things in different ways, sound can trigger the gambling addicts as well as pictures, smells, and memories. It works on people in different ways. What you think about before going to bed and while working will also play some role later.
Be intentional about your thoughts and if you think you are expereince some symptoms of early gambling addiction, talk to someone you know that can help.
Although you have a point but this doesn't apply to everyone, there are people that are experienced and been gambling for a long time but they still make certain mistakes that a beginner would make...sometimes it's not even a matter of experience but it's lack of self control and greed..But like you said, it's possible to seek help when you detect gambling addiction at an early stage, when it gets used to you it would be a problem.