Most climbing sacks from the top end of the market are as strong as the Mil-Spec stuff.
I respectfully disagree. For basic backpacking/hiking, sure, but not if your pack is dumped on a pallet with 50 other packs and loaded into a cargo plane. Then dragged/humped from here to gone. Not every person here (or anywhere) has the same uses as the next. Hence, the range of gear available.