[jacobmuller]

Whatever weapon you buy, if it's meant to have a sheath, it's included. But if you lose, damage or otherwise need to buy a sheath, then it's 20% of the cost of that weapon. If you buy a fancy sword, they give you a better sheath.
Isn't there an option for poorer quality, lighter sheaths and the detriment to weapon health?

A sheath that weighs 50% of the weapon weight does seem excessive - must go weigh my sword & wooden sheath... 2.2lbs total, 1.76lb sword, 0.44lb sheath. I've never done that before - never even thought about the weight. But that's 4/1 not 2/1