How Should We Treat Drug Addiction?

It genetically eradicate such people from our genome.  

That's noble but wishful thinking. If you look at the root cause of drug behaviour you would have to try and eliminate those with a weak constitution who cannot rise above their circumstances and are dragged into an escapable web of spiralling self-medication. You are right about recreational users who have egos as fat as their wallets and use cocaine to "enhance" their living experience. Most of them get away from the dependance and look at it as a time in their lives when it was a means to an end. What the heck...they have loads of money and those rehab places are more like exclusive high-end resorts where the elite showbiz community have great holidays.

Rock stars are a glowing example....my guitar hero of all time is Jimmy Page who soared the heights. From a very young age, everything he touched turned to gold and by his own admission, enjoyed every moment of it. By the time his band folded he was a heavy heroin addict but looking at him now, he is a very, wealthy, wise, articulate man with an honorary professorship and still puts a lot back into the industry he has always been in. Others, you could say, are not much loved in the industry............What is the difference between a two year-old boy and a bag of cocaine........Eric Clapton would never dare let a bag of cocaine fall from the 53rd floor of an apartment building.