Of course gambling addiction is not spiritual. I think it's just greed on most gamblers part. Most gamblers don't know when to walk away and as a gambler you must know when to walk away whether you're on a winning steak or losing.
But the Oliver twist in some people will urge them to want more and keep going especially when they are losing to try and win back their losses which can be addicting.
Gambling success is based off of statistical analysis and pure luck, if you have this understanding, you will always stick to your predetermined limits.