I agree with what most have already said, especially the misconception that a lighter pack is going to be less comfortable than a heavier pack. I'll also add that, if your thought process is, "so what if my pack is two lbs. heavier, it's only two lbs.", than does that thought process continue with everything in your pack? If this is the case, you may be carrying a fully loaded pack that weighs quite a few lbs. more than the next person that is counting every oz. When I went on my first sheep hunt, my pack weighed about 70 lbs. for a 10 day hunt. By way of comparison, to do that same hunt today, my pack weighs around 50 lbs. A 25-30% reduction in the initial wt. of my pack, since I started counting oz., is pretty significant IMO.
Oh, and the 5 lb. pack that I carry today is MUCH more comfortable than the 7 1/2 lb. pack that I started with years ago.