When desire for outcomes overcomes fears.
See this article, Poll Shows 74% Support Aerial Surveillance in Baltimore. Note that it does not specifically call out drones, but three small aircraft — which might not be drones. Admittedly, the survey might not be the best in the world, but it is an indicator that the progression for the use of drones in cities will not necessarily only be driven by next-day delivery of packages by Amazon, UPS or FedEx.
There are many hurdles to any implementation and I would expect lawsuits by persons and organizations concerned about privacy. However, I think many times science fiction is a good prognosticator of what is possible with technology in the future.
Likely not in my lifetime, but certainly my grandkids' lifetimes.