Is there an in-universe reason why so few Harry Potter characters smoke?

Question

Very few wizards smoke in Harry Potter.

However, drinking is glorified and quite regular.

Is there an in-universe reason for this disparity of the Wizard World to the Muggle world, where smoking is more common?

Answer 1

As mentioned in the comments, smoking is far more taboo than alcohol in the UK — more so since the smoking ban in 2006, but still taboo for children in the early 1990s.

The Harry Potter series (1–7) is essentially a boarding school / coming-of-age story with magic. Coming-of-age types of stories typically (in the UK, at least) only feature children smoking in illicit contexts, such as behind the bike sheds or amongst a gang of delinquents.

For example, Michael Frayn's Spies features children who at one point smoke in a hidden location, but in this case the plot revolves around a couple of kids using that place to spy on an adult. The under-age smoking in this context fits in with the secrecy and loss of innocence.

In Harry Potter (as mentioned in Valorum's answer to the linked question), Dudley and his friends smoke, which adds to the general image of their delinquent nature, because teenage smoking is taboo. The reader certainly wouldn't expect a law-abiding character like Hermione to smoke. If she did, the reader would gain a completely different impression of her. (There's no save-the-world-from-evil excuse for such a breach.) The plot doesn't revolve around three kids experimenting behind the bikebroom shed.

On the other hand, teenagers drinking certain types of alcoholic drinks was quite acceptable in the early 1990s in the UK (and possibly still is). For example, a glass of wine at a meal with adults, pimms in the summer, mulled wine at Christmas or champagne at a wedding reception. Hard stuff was (and still is) taboo. A kid sneaking a bottle of vodka into school was also likely to smoke and be considered a trouble-maker.

All the instances of smoking listed in the other answer fit in with the setting and show something about the character. (Dudley's a thug, a woman smoking a pipe is eccentric, etc.) Although the magical world does have some different customs from the muggle world, it's likely that teenage smoking is a taboo they share, otherwise the narrative (which is mostly from Harry's point of view) would note the difference.

The other thing that's noteworthy in Valorum's answer (just considering the books 1–7) is that all the characters in the wizarding world who smoke seem to use pipes, which fits in with smoking in common fantasy settings (such as in Lord of the Rings).

Rand al'Thor's comment is also quite pertinent:

I'd add that Fred and George do seem like the type who might be smokers in a Muggle school. Maybe they got their kicks from magical troublemaking instead (fireworks, anyone?) ... and in fact that could be another general factor why we don't see much smoking at Hogwarts: the kids with a tendency for delinquency would be more likely to, for example, experiment with banned spells or potions than anything so mundane as cigarettes.

Also b_jonas's comment provides a quote from JKR in 2001 about her own childhood smoking and her attempt to conceal it, which illustrates that at the time she was fully aware that it was illicit and would get her into trouble if she was discovered:

I remember hanging out of my bedroom window smoking behind the curtains late at night. My father will not be happy to hear that. I wasn't very clever about that, either, because, you know, I used to leave the cigarette the cigarette ends were, you know, below the window, I mean, ‘Oh yeah someone from the pub, dad, has been throwing them into the garden again.’