When I used to drink like a student, while I was a student, I wouldn't tend to take insulin for alcohol (unless it was a cocktail night and no dancing), but would always reduce insulin for evening meals (when out drinking) and would always require a bedtime snack and would also tend to be low in the morning. It was certainly partly the alcohol, but also the being out dancing, walking around between bars, etc., has a definite effect on stopping the immediate effects of beer raising blood glucose levels.
I don't tend to drink very often these days, but I'd not bolus for wine (unless it's sweet and lots, yuck) or I'm eating snacky things with it, I will generally bolus something for beer though I usually wait to see what happens after the first pint (as I only drink when out plus beers are different, so BG may decide to go up or just be happily flat). I would definitely bolus for cider.
I don't drink enough to worry about overnight effects these days, but I do have an inkling that my FotF started when I gave up the habitual after work glass or two or three of wine a couple of years back.