I have even heard the argument that only abnormal people were buried in the neolithic. Following this logic we can assume that remains that appear normal are abnormal in ways that are not preserved (like the skin or behavior)
I heard a argument about swords comparing to clothes.
Useful clothes you use daily and later recycle it. Wedding dress you preserve.
Swords was probably the same thing, the useful one is used in battles and the metal recycle, the special ones was preserved.