Some people in Oregon have already started a Class Action Lawsuit against Google after Google came forward and admitted to having accidentally stored more information then they had intended to gather when going around gathering information for their StreetView application.
Now i'm NO law guru, nor have I ever studied law. My following comments are going based on the ethics or general behavior of society. (society being used very loosely)
If i were to stand on the sidewalk outside of your house and write down your address, or even walked up your driveway to write down your address, there would be nobody pointing their finger at me crying foul.
With this same regard, people should also be okay with the idea that someone came by and looked the Mac Address of their Wireless Access Point. Right?
If i were to look into your windows from the sidewalk and see your furniture, or even your family, inside your house, i would not have the police knocking at my door coming to arrest meor even a fine in the mail. If you're the kind of person okay with people seeing into your home, then in that same respect it should be okay for someone to see what's going on in the traffic of your wireless network.
Is it polite to sit there and look into someone's house? Probably not, i wouldn't like it if someone i didn't know was looking into my home. But i would put up blinds to keep them from being able to view into my home. The same way i would put encryption on my network to keep them from being able to view into my packets.
You wouldn't consider it stealing if you went and looked at someone's address on the side of their house. So it also shouldn't be considered stealing for looking at their mac address on the network.
You wouldn't consider it stealing if you peaked into someone's window, unless maybe if they had a "no trespassing" sign. (and no i'm not talking about walking right up to their window standing ON their lawn) So it shouldn't be considered stealing for catching glimpse of traffic going on on their network.
I've been in the garage working before, or even in my living room with the door cracked or open with my music loud, and I've had people who were looking for my dad walked into my house/garage and ask me "does my dad's name live here?". I understood they chose to walk right in because i wasn't responding to the normally accepted way of contacting people at their home, doorbells and knocking, but I found it kind of awkward, and was startled when this happened. I didn't go calling the cops trying to get a free handout, or try to get that company fined by the government. Instead? I closed the garage. I closed the front door and locked it. And with my Wireless Access Point, i put a password on it so people can't connect without me first giving them the password.
I'm Sueing!
I'm really not. If you want your networks private, make them private. If you don't know how, pay someone to do it the same way you'd pay someone to install blinds on your windows and locks on your doors.
Wireless Access Points go one step further and allow you to not broadcast your SSID name, which would be the home equivelant of cloaking your house and making it disappear off of the lot!
There is NO reason why people should be trying to get a free handout.
Lets say it was Christmas time and you decorated the outside of your house amazingly well. I take a picture because i'm in awe, and i am at home with my buddies showing them pictures only to have someone point out that you and your spouse could be seen through the window "rubber necking". I immediately remove that picture from my album of pictures i'm showing my friends, and write you an apology for the friends that had already seen it. Are you going to sue me? Could you? Should you?
That is essentially the same thing that Google did. They found the issue, assumingly removed it from public consumption, and made apologies to people who may have been affected by it.
That should be the end of it.
They could go out of their way to publish thorough tutorials\documentation on how to secure your networks, or even go a step further and allow you a way to "opt-out", but there should be no Class Action Lawsuits.