They're aware of the signs of gambling addiction, but still lack self control. A responsible gambler with a plan would recognize when they are losing too much and take steps to prevent addiction, without needing from others. As the saying goes, A good person advises themselves after all self reflection and introspection can be more valuable than advise from others.
You know that most gamblers could actually know that they are addicted or having the symptoms of addiction in their gambling lifestyle but even when they want to stop they can not help it, those people actually need an additional help from love ones to guide them through and that why when some of them can not get help, they become worse.