If you have a small enough town with a small enough cell size, it should be blindingly obvious which handset IMSI numbers where usually in the area when a crime was committed.
With enough data, you can simply map out the handset IMSI of the most probable perpetrators. There were 5 instances of a street robbery, at night, and the only common denominator is IMSI xyz that has been in the vicinity and moving around the time of all 5 robberies. It either is a totally unlucky individual or the most likely suspect.
Follow that IMSI with a drone for a few nights, record evidence and then lock these people away.
Note that I don't mind any and all police activity directed against common street thugs, as long as they have reliable evidence against them. (not dealers, not pimps, not smugglers, maybe not even thieves - but violent criminals that assault and rob innocent people or even invade their homes deserve absolutely no mercy.)