They implemented in at least one store in a Seattle suburb. I'm not a wine drinker, so I just know they had a flyer for it a few years ago. I don't know if it is still on-going. But your point stands: I don't know that one can flip baristas to sommeliers with a switch at 5:00. So is there a shift change? Employees are trained on both? I dunno, I applaud the thinking, but don't know that it's practical. I should run up to the Woodinville SBUX sometime and see if they're still doing it.
Pivoting into wine is easier than dinner.
And a lot of Starbucks’ customers would like a wine bar and don’t have great alternatives in many areas.
Only issue I could see is that a lot of places don’t let you take alcohol out of the bar you served it at.
https://www.foodandwine.com/news/starbucks-reserve-store-sea...
It makes sense although I suspect it's more difficult than is obvious to handle rather different uses at different times of the day. (It's also probably notable that they're doing this in locations that are already pretty differentiated from the standard grab a Cafe Latte in a paper cup on the way into work.)
As I recall, Starbucks actually looked into doing some sort of wine bar transformation in the evenings at some locations. But I've never seen such a thing so it presumably didn't work out for whatever reason. And that's a single business.