Those are the standard arguments, they may be effective for some, they certainly help discourage many who haven't used yet or used only lightly and intermittently, but they obviously aren't 100% effective and everyone knows them, so someone still using presumably didn't find them compelling enough. They might be real close, and maybe on the downward spiral they'll eventually be enough, but the goal is to catch as many people as close to the top of the spiral as possible. I think you're ignoring the victimhood aspect too, drugs are actually insanely cheap, government regulations and taxes make them expensive, and people know this. Tobacco, coffee, cocaine, opium, are all things that with modern tech barring if legal and not sin taxed could be supported as habits for the price of a can of soda a day. To them, especially with the addiction in place, the price and social costs are externally imposed and it is not actually illogical to resent that nor to counter 'people commit crimes on it' with the exact same argument used for booze, "If and when I do that becomes an issue". We use a 'For your own good' approach that while legitimate often comes off smug and wrong-headed, and thus ineffective. If you can offer them a clear 'for your own good, your choice' that doesn't revolve around dim and distant futures or costs that exist because society imposes them, I'd think they'd be more effective, and they can be supplemental rather than substitutes.
They'll generally gravitate to circles where it is acceptable, which of course has the other problem that it tend snot to just be acceptable but encouraged and reinforced and twinned to other 'acceptable here' crimes like robbery and fraud.
- Albert Einstein
King of Cairhien 20-7-2
Chancellor of the Landsraad, Archduke of Is'Mod