I understand it's been done too. But my understanding is, it takes many hours and some seriously highend equipment. In fact, if I'm not mistaken, the article I read stated it look a cluster of highend something like 6 to 10 hours to crack WPA2.
You certainly won't be doing it quickly with a laptop while war driving around someone's neighbourhood in your car.
Besides, the people who want to use wifi for nefarious purposes know there are many, many "free" wifi hotspots out there to use so why, pray tell, would they bother wasting the necessary time to crack someone's WPA2 encryped WLAN. Simple answer is, they won't. They drive over to the nearest coffee shop (or whatever business) with the free wifi and they'll go in, buy a coffee and sit there and do whatever.
Using WPA2 encryption in a home situation is adequate protection against people with nefarious intent. You can make it more secure by using a complex key, a complex SSID, and by hiding the SSID. If you're really paranoid, you can also set your WLAN to only allow devices with MAC addresses you define to connect to your WLAN but personally, I think that's a bit of overkill myself.
WiFi is not "new" by any stretch of the imagination. Is it harmful? Perhaps if you duct tape a wireless router to your head and leave it there for a few years it might be. But making sweeping statements like that without proof is just heresay and of NO value. So unless you have several (as in, not just one) bonafide cases of injury from wireless, please keep your conspiracy theorist/doomsayer opinion to yourself.
As to power consumption. Shutting the wireless side of a router down won't save jack if it's still plugged in. Besides, if you really want to save money on electrical, you'll want to shut all the other electrical devices in your house down that consume a steady amount of power 24/7....like your TV, home theatre, stereo etc. Shutting down just your router won't save enough to matter.
It matters not how straight the gate,
How charged with punishments the scroll,
I am the master of my fate;
I am the captain of my soul.