That's true, but I think that's an overlooked factor in some other "lifestyle choices" as well. For example, people who significantly reduce their alcohol consumption often report changing social groups and activities to do so, so in at least some cases it can be a package deal. I don't think there are very many choices that are completely isolated, independent from all other choices, and free of consequence on any other aspect of your life, though there's definitely a spectrum of being more or less so.