Marijuana was banned to target minorities, but alcohol prohibition mostly was repealed not because white people like alcohol, but because alcohol is stupidly easy to make from a wide variety of substances so most cultures around the world produce some kind of alcohol with their local crops. You can use pretty much anything sugary: fruit (wine), honey (mead), and grains like rice and wheat (sake & beer). It is really hard to ban a substance when half the foods in our diet can be turned into that substance if you let it sit in a jar or bucket in your closet for a few weeks.

Prohibition was repealed primarily because it was a futile effort and with alcohol being banned, very strong distilled spirits were the economical way to discreetly transport and serve alcohol since it is easier to hide a few bottles of liquor from authorities searching your truck or business than to hide large barrels of low ABV drinks like humans had been brewing and drinking for millennia. It is also a lot easier for people to drink themselves sick with distilled drinks, so ultimately it was decided that it was safer to make alcohol legal and regulated instead of having it still plentiful, but getting people sicker and funding criminal empires. It’s a lot easier to ban one plant than to ban every food source with sugar in it.