It seems likely this is about homeless, if you have a car you often have a home or apartment where you use.  But you are right, these centers will be counterproductive and dangerous if they don't think through things like how to stop an addict from driving away, or what to do if it's obvious there has been theft to support the habit.  The centers will not work if the addicts believe there will be law enforcement, even of collateral crimes.  But turning a blind eye to crimes other than the drug use will make them crime centers.  What about selling?  The centers need to be clear that people can't sell opioids on the sidewalk outside their doors.  

I sympathize with these neighborhoods trying to isolate drug use and take back some of the public space, but I'm afraid this will be too complex.  Probably the "traditional" solution of firmer law enforcement coupled with rehab is the only was to address this.