Of my last 20 dungeon runs where I didn't tank, maybe 2 didn't do speed pulls. And those 2 were low level dungeons such as Tam Tara. You should actually expect speed runs and just speak up if you don't want to do it and maybe the tank will be nice about it.

I personally love killing stuff faster and faster as my gear improves or seeing how much more I can heal or how much more I can survive. Big pulls accomplish this.