Alcoholism is an option, but harder drugs generally are more expensive.
Are you sure? In my experience, a tab of acid costs $5-10, and the effects last about 5 hours. That's way cheaper than alcohol. [1] shows a breakdown of cost per hour for a bunch of drugs I've never touched, and most of them look to be pretty cheap under this metric. Compared to movies, sitting around in coffee shops, etc., they're remarkably cheaper than a lot of legal forms of entertainment.
[1] https://www.addictionresource.net/blog/cost-of-illegal-drugs...