People drink because it's the cheapest entertainment. When people have more money they try out other forms of entertainment.
I imagine rich people use alcohol to spice up other entertainment and poor people more often entertain themselves with alcohol only.
These are the top Google results for "alcohol consumption by income level", by the way. There's no need to speculate about it without sources as people in this thread are doing.
So just add to the "basic income" scheme a "basic mental health" package, and where are good to go.
Personally, I don't see how UBI scales beyond small tests to whole countries/economies.
I do wonder though if it would be possible to fund with a combination of a sell off of public land plus technology. Theoretically, with a UBI, there would be little to no need for the government to provide subsidized housing, and a technological solution where money could be sent directly to landlords rather than via recipients would provide the sort of risk reduction that many landlords need. That could lead to a boom in sub $1,000 a month rentals, where landlords are guaranteed they will be paid.
Combine with a sell off of some public housing assets, and it might be possible to fund a UBI for several years, not so much to push the can down the line, but to see if the trillion dollars is recouped with economic growth as the entire amount would be spent by all recipients up to and slightly above the median US income, so there should be some positive economic growth.
That's the rub though, this is hard to pass. The left in particular won't like the replacement of programs for direct cash and a public assets sell off is kind of the left's idea of heresy. Conversely, the right won't let it through without MASSIVELY reducing the number of programs that are currently funded. There is virtually no country in the world with a sane and rational enough parliament to be able to perform the sort of radical surgery their budgets need to introduce a UBI.
I'm slightly suspicious of the self-reported drinking levels. I'd be afraid that the aid recipients might fear having the money taken away from them (no matter how much they're assured otherwise) if they report their true amounts of drinking or other behavior they assume the study organizers don't approve of. Do surveys of people who drink typically reveal true results, when further investigation is done?
The incentives here are so painfully slanted. Is there a B Team investigating this adversarially? Ideally this study would be done by researchers who aren't true believers in basic income. If it really works, it works when those carrying it out don't believe in it.
Especially considering that if this does get implemented globally, a big percent of those running the show will be bored bureaucrats, not people passionate about the fate of the impoverished.