I'm not sure i can post links yet, but im gonna try anyway
if it doesnt work, try searching switzerland drug use policy,
aside from whats described in the article, it should be noted that the government views drug use as a disease
this greatly reduces the view held often by younger illegal users that using drugs is "cool"
which i think stops a lot of people getting into it in the first place.
I'm from the netherlands myself and here cannabis in general is allowed, and the sales are being controlled by certified sellers (although small amounts may be homegrown at your own discretion), strangely enough, they're called coffee shops. so referring to ita, they wont be sold to minors easily. thats not to say they dont get their hands on it for sure, and there are still people who certainly get addicted to drugs, only not to cannabis. cannabis has scientifically been proven non-addictive.
fact is though, that families who are open minded often experience less difficulties with drug abuse, and a less strict policy and these types of thing usually result in people less interested in them.
a less conservative stance on drugs is, in my opinion, a safer way to deal with it.
this stuff is often used by people who have a hard time dealing with reality, and use it to escape from it for a certain while.
unforunately, this is somewhat of a self fulfilling prophecy in a country who considers these practices criminal, because that will result in more problems in your own life, means more stress means more need for drugs, kind of a vicious cycle empowering itself.
the root of this problem, is not the stance of the government, its the problems people are having and their need to escape. the stance a government takes is capable of either relieving the stress of a person, or increase it.
disclaimer; the views expressed in this reply are expressly my own, aside from the article from reuters, i have not double checked my facts and i may certainly be wrong.