It's highly likely that there is a genetic component to addiction.
This sounds like eugenics -- and the Wikipedia entry on the charity [0] is also somewhat disturbing. However, is this really any different from handing out free condoms?
The aim appears to be more about stopping children being born with defects caused by the parents' drug use, and stopping children being born to unsuitable parents.
Tackling world overpopulation will be achieved by far more controversial methods than birth control of a minority group...