The first comment at the source alleges that Google designed that in... they did war driving as they videoed, and grabbed neighborhood peripheral data as they went, from people who hadn’t bothered to password protect their networks.
That was pretty presumptuous of Google. I do not know what they hoped to accomplish by doing this. “Dear john@doghouse.com: we took note of your email address while we were going down Main Street in Hackersville, USA. Please look at our photos of this street and let us know if you like them.”
Funny thing, though, a degree of snooping that might get an individual thrown in jail results in a fine that is a pittance for a corporation like Google.
They were collecting wifi network names (SSID) and their locations so that they could use that data to help user geolocate themselves more quickly. The other data came along for the ride. People should have encryption enabled on their networks anyway. What google did is more analogous to recording CB radio transmissions than wiretapping.