It’s the same reason militaries scout terrain before moving troops. You don’t wander blind into an ambush. You map the field.
https://untraceabledigitaldissident.com/how-to-map-a-surveillance-net...
A few weeks ago I saw a gentleman walking down a main street here taking pictures of the CCTV cameras that are at various intersections in the road. He was walking the same path as me so I watched him do this for a few minutes. I thought about asking him why he was doing that but then I minded my own busienss.
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