Any good tanking guide out there will let you know that maintaining agro is top priority. The better guides out there will also let you know that you get so many tools to establish agro, that your top priority is also the easiest thing in groups for you to accomplish. Because of this, extensive guides will indeed focus on putting out more damage. It's what actually brings intricate, engaging gameplay into tanking.
I have witnessed tanks get harassed for staying in tank stance in normal duties, but that is about the extent of it. I got trolled one time, but that had nothing to do with my damage output. I do agree that it is odd that anyone would give this kind of grief to a tank, especially after sitting in the queue for a long time. But no one in any of the PUGs I've been in were dumb enough to actually kick the tank for such reasons. I definitely feel it is a role that requires a good set of armor. Both inside and outside the game.
