I imagine the shelf checkout won't be as much looting as you all expect. Probably got some people watching it. I mean self checkout is everywhere such as grocery stores. Only downside for Apple is the sheer amount of traffic that makes most stores look like a mosh pit.
I think alot of shoplifting is a crime of opportunity. I think people would be less likely to try in an Apple retail store because the open floor plan. I also think that the huge crowds are a deterrent since they would cause a scene and major embarrassment.
The people I knew who shoplifted in grade school did it stores where they couldn't be seen by employees or other customers and without crowds to cause embarrassment. Funny when one guy got caught, he was paraded through the mall by security. He never stole again.
I'm not saying people won't try it, but most realize the potential to get caught and the resulting embarrassment is not worth it for a $30 case.
* This sales system definitely seems like it was planned by Steve, trusting in the greater good of humanity.