You make a good point. I think of these more like a feed back loop. One can affect the other. You can spiral up, or spiral down. Some people might be genetical

You make a good point. I think of these more like a feed back loop. One can affect the other. You can spiral up, or spiral down. Some people might be genetically predisposed to become Alcoholics. Once you start drinking more, it will make you more of an alcoholic. Drinking less, will make you less of an alcoholic. Social pressure might help you drink less, or drink more. Its not inconsistent.