When I was quite a bit younger and did a semester abroad (from the US) I became friends with several Dutch students in our dorm/hostel. I remember, being the naive 19-year-old that I was, asking how cool it was that weed was legal there and stuff like that. They mostly looked at me with a tolerant but exhausted expression and said that it was more of a tourist thing. The impression I got was that it was treated by everyone the way I now look at teens who constantly talk about smoking cannabis or getting drunk as if it was the coolest thing ever. Basically it was like "yeah, sure, it's legal but come on, only dipshits make it out to be something more than a minor vice or guilty pleasure to be indulged infrequently".
I wonder if this is related to quality of life. A country like the Netherlands with stronger social services/safety nets and more 'liveable' cities must have much better quality of life for the bottom quintile of society compared to the states, and it's that quintile that is most likely to get addicted/cause other social problems.
It seems like a common thread through people getting addicted to drugs is trying to find an escape for a crappy/desperate life, so logically if it's less crappy people won't need an escape as much, right?