Reader Lauren Weinstein found a blog post that gives a good, fairly technical explanation of why Google's collection of Wi-Fi payload data was incidental, and why it's easy to collect Wi-Fi payload data accidentally
in the course of mapping Wi-Fi access points. "Although some people are suspicious of their explanation, Google is almost certainly telling the truth when it claims it was an accident. The technology for Wi-Fi scanning means it's easy to inadvertently capture too much information, and be unaware of it. ... It's really easy to protect your data: simply turn on WPA. This completely stops Google (or anybody else) from spying on your private data. ... Laws against this won't stop the bad guys (hackers). They will only unfairly punish good guys (like Google) whenever they make a mistake. ... [A]nybody who has experience in Wi-Fi mapping would believe Google. Data packets help Google find more access-points and triangulate them, yet the payload of the packets do nothing useful for Google because they are only fragments."