[e12e]

> What's the difference between such surveillance and a security guard wondering around looking for suspicious activity and/or protecting shoppers/businesses?

Scale and awareness?

Scale, because if you ask that guard, who was buying what with whom, 742 days ago, chances are that guard won't be able to answer in any meaningful way. A database might (if eg: indexed on biometrics).

Awareness, because we come to ignore cameras, while if someone is actually there, looking at you, you are aware of being watched. (And also aware when their back is turned, so you can sneak a kiss from your mistress, or whatever you're not comfortable doing "on the permanent record" -- but might not be wrong).