I wonder what it is in West/Central European cultures that make them relatively tolerant of prostitution, even publicly. Just mentioning something like this in Sweden would be unthinkable.
Zurich used to have a really bad crime problem associated wiith drug addicts. Google 'needle park'. They started to provide the drugs for free in clinics, tied with option conselling, etc. The difference is really remarkable. Now, Zurich feels much safer than most other cities it's size.
This seems to be a similar approach, based on the good results of their drug policy.