I have certainly encountered a variety of pack-strap noise with different packs: scratches, squeaks, etc. It's not particularly uncommon, but neither is it universal (as you know from your previous packs).
A lot of times a noisy packstrap indicates an imperfect fit. Sometimes that imperfection can be adjusted away. Sometimes, the pack just needs to be returned for a quieter model (or customized, as you suggest). Overloading a pack can also make it noisier.
It's easy to be a holy man on top of a mountain.
-- Larry Darrell