Only a minority of those who use a given drug ever become dependent - even for heroin, less than a quarter of those who have ever used it ever became dependent.
Oh? So you think you ought to be able to decide what portion of the population is expendable?
I don't have to - they decide themselves with every pre-addiction high they choose to engage in.
Stuff like this is why I don't like wasting time on you. Once they get high, their brain short circuits their free will. Thereafter most of them are just worms responding to stimulus.
You can't play games with an organ that runs on chemicals by tampering with it's chemistry. It doesn't function correctly after that.