Just about any sensor you can think of can be used for spying. Are the logistics of recovering camera film from spy satellites something you think about every time you use the digital camera in your smartphone though?
I love to read these kind of stories, It's hard to quit everything in life and pursue a new way of living. Not everybody has the guts to do it. I fall in this group of people that are too afraid for the unknown and sit in the job not seeing the point of it almost everyday.