Have to include alcoholics in that one. Also prescription uppers and downers. Those are the three biggies for people that need a chemical crutch.
Don't forget pop/soda, coffee / tea and candies and food or lotto tickets, or shopping, or any of the millions of other activities people use to get by, to get high, to help make life more enjoyable. All of which for some people get out of control, while for others they don't.