Ouch. I only heard about these shops recently, when I saw a photo of one on facebook. I was amazed that the council allowed them - but then I am also amazed that they allow massage parlours.
When it became illegal to drink and drive, teens turned to drugs. The risk-taking years for many of them last for around ten years, after that I suppose now we just have to be grateful that any are still alive and not brain-damaged. I think it's impossible to stop, but whoever allowed those shops to open should be shot.
However, as the ex-wife of an alcoholic, I once felt the same about pubs and off-licences. I told my DCs all I knew about alcohol and drugs, made them read up about them and they attended many talks and workshops. DD admitted to a few months of cannabis-smoking when with an Ex, but DS is dead against drugs and rarely drinks. I hope my DD will instill enough sense into my GCs to keep them safe, and give them enough confidence to not succumb to peer pressure, which I feel is the main problem. I can remember very clearly not being invited to many parties as a teenager because I didn't approve of drug-taking, and was once evicted from one for throwing dope buns out of a bathroom window. Someone accused me of cruelty to birds!