I agree. I mean there have been cases in Jo’s books that do say about acohol, but I don’t think that the Professors in Hogwarts would allow a couple of teenage boys getting drunk, ecspecialy boys with a record of breaking schools rules. Also, i do recall in the third book that Harry said that his father wasn’t a drunk. Maybe James did drink wine from time to time, but I can’t see a great wizard like him going behind everyone’s back and get drunk. I can see him harrassing others and such, and mayb ehe did taste test a couple of acoholic beverages, but I really don’t believe that he would get drunk. Though my case is not sure with out asking J.K Rowling herself, it is and excelent question, that I have thought about a few times, but never really asked anyone.
Seems to me that they do have the risk of firewhiskey being smuggled in. When the DA meets at the Hog’s Head Ron says he thinks the barman would serve them firewhiskey. I agree that Sirius definitely seems to be the type to spike the punch, iykwim! I think they do have drugs, but they are possibly different than Muggle drugs, because they have potions and magic plants that produce different, or maybe similar effects. Muggle drugs (druggles?) are probably inferior or even looked at as silly, pointless.
It could explain why some wizards from good families ended up in the Death Eaters or Azkaban though. Potion addictions?
As for the smoking- it was socially acceptable in our world for a long time, and still is in many places. Many adults from earlier generations do not question it in others b/c it became such a huge part of the culture. The pipe smoking especially was practically required among some classes as an after-dinner ritual. Jo (and I) may be showing age in that detail.
It would have been more potion consumption than drug consumption, wouldn’t it? And there were slight implications at alcohol-related buzzes from Butterbeer. Not to mention that Dobby said house elves could get tipsy on it faster than wizards…. I would think its taboo just like it is for muggles, but there are probably just different circumstances….