You have no prove about that.
False, you are forgetting leveling/questing/profession skilling people who don't want to bother with pvp.
You don't know how pve servers work then. They don't disable anything. They allow you to choose if you want to do wpvp or not. Do you want it? Flag yourself. You don't? Toggle it off and people can't attack you in contested zones. In pvp servers you simply don't choose, you are just forced.
Come on, you see those kind of shouts once in a while, only a fraction of other spammed activities.