That's the point. You don't need for people not to be able to see to feel private. You just need to not be forced to acknowledge them. As illustrated by the people going to the bathroom, the people hanging the tie on the door, the reality television stars finding privacy while on camera and the Asian who finds privacy behind a translucent sheet of paper. When push comes to shove, it doesn't matter that they can see, as long as you don't have to acknowledge them.
I consider the current situation where we're working as a culture to create new taboo's to cope with "cyber-bullying" as the beginning of the process.