Cell tower locations are useless since they bonce around when full. Now if they can localize a phone during an investigation, by turning the GPS on. then what you and the others say would be correct.
They are tracking you...they know what cell towers you are hitting. they can deduce a patter of your usage or even anomalies if you go somewhere on vacation or hunting in the north woods or whatever.
They don’t need to track you down to the millimeter, a quarter mile is more than close enough.