Let me take that.
One of the reasons that Google doesn't trouble us as much as other types of surveillance is that their surveillance is at a certain point in time. If you allow Google to use the argument that it's a journalistic exercise, then it's perhaps a small step for a company, instead of taking images at a point in time, to install cameras at some location and to catch people going past that point 24 hours day, 365 days a week. Then I think you can maybe see potential harm, because then you could discover that a particular person goes by that point every day at that time.