Regarding 'young people', keep in mind that children were thrust into the adult world a lot earlier in those days. In the UK most had left school and started a full time job by the age of 13, and it was only very recently that society had begun to accept that children were especially vulnerable and in need of protection by law. Before changes in the Law which were enforced from 1909, it was perfectly legal to sell tobacco and strong drink to a child of any age who came into a pub or shop with the necessary funds in hand, and that gives some idea of the level of social acceptability of smoking and drinking by those of tender years.
Under the new Laws which were still something of a novelty in 1912, tobacco products could not be sold to a child under 16, unless (and this was a big loophole) there was no reason to suppose that the child intended the weed for personal consumption ("It's for my Dad". "Fair enough"). Persons under the age of 14 were excluded from licensed premises like pubs which were in business mainly or wholly to supply strong drink, but the law did not disapprove of children drinking alcohol elsewhere unless they were under the age of 5. I imagine that the same sort of restrictions (and freedoms) would have applied on board British-registered ships.
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