.....plain and simple
It isn't though, that's what people don't seem to realise!
For example, following the death of my brother 8 years ago my parents started taking sleeping pills. It was the only way they could find to get them through those terrible first months and years after his death. It became their coping mechanism. My Father is a Barrister and my Mother is a GP, so although they work under a fair amount of pressure day-to-day, they are educated people, and financially speaking they have no problems.
But, they've been left mentally ravished by something that happened to someone they loved, and despite all the help money can buy, they are still left with dreams that will haunt them until their death.
My point is that each case is different, and you're a fool if you simply class an addict as an addict without truly understanding the circumstances that led to their addiction.