I think the fact that the guy actually took his laptop and went and stood on a random street to connect to an unsecured network makes it very different to a person in their own home connecting to their neighbours unsecured network. But both are some degree of stealing.
And Dolly, to answer your question, when you set up a wireless network the settings will ask you if you want to put a password on it to protect it. So to compare it with you carelesssly leaving your door open and someone walking off with your TV isn't right.
If every time you walked away from your front door, leaving it open, it asked you if you wanted to leave it open or shut it. And then you chose to leave it open, then you would be fully aware that the door was open, and it wasn't just you forgetting to close it. You had the chance to close the door, but didn't do it.
I don't know if I explained that too well. It makes sense to me though. If it doesn't make sense to anyone, then I will try and explain again.