That's a nice picture of some guys back. It does happen all the time though, I have been in voice chat on pretty much every faction and heard people getting reports from their spys on the other team. For some reason people think they are so very smart for having the idea to log into another toon and report enemy movements, when in reality everyone has had that idea before, but they have the self respect to not do it.
Most people don't do it because its a waste of time, there is nothing you can't learn from the map that you can learn from spying.
Spoiler Alert: Nardle dies in the next episode of Game of Thrones. On the topic: finally, a definite proof! sharpen your pitchforks, ignite your torches!