See my comment here: https://news.ycombinator.com/item?id=8542155. In fact, at the time prohibition was proposed, alcohol taxes made up fully 1/3 of federal revenue. The money and moneyed interests were aligned against prohibition, not for it.
I think a lot of people look for ways to get around the fact that when you give people self-determination as a group, they might vote for things you don't like with no nefarious undertones in play. The simplest explanation is this one: I don't vote, my mom does. There are more puritanical people who simply don't want to live in a society that condones drug use than the opposite. It's just like how when people in arab countries got the opportunity to vote, they voted-in conservative Islamic governments. Sure they are opportunists taking advantage of those tendencies, but at the end of the day, you have to grapple with the real fact that people have ideas about what their societies should look like, and democracy means that they get to carry those ideas into fruition.