Do you actually think that driving down the street with a parabolic mic and recording people’s conversations is a legitimate thing to do? And does the claim that you’re doing it as part of a “population density study” somehow justify it? As opposed to doing it, say, for the purpose of collecting personal information?
Most people don’t know how vulnerable they are when they use computers, the internet, Wi-Fi and so on. I’m old fashioned, I know, but I don’t think that means that exploiting their vulnerability is justified. You may be more sophisticated when it comes to using computers than most but there are still a great many people who are more sophisticated than you when it comes to law, finance, real estate and lots of other stuff. I bet you don’t enjoy it when they pull a fast one on you.
I am not going to form a conclusion about this yet but, I think that the technicians working on Google’s behalf were probably aware of what they were receiving with their antennas, what was being recorded on their hard drives and what they were downloading to Google’s servers when they were done. If Google’s defense is something like “we made a mistake” and you buy that, well, what can I say but 'more power to you'.