Just because rarity ≠ price, it doesn’t mean that it’s meaningless.
People want to know for no other reason than “wanting to know”
Saying that relative rarity is meaningless is like saying that knowing how tall the pyramids are and comparing them to the heights of other historical structures through is meaningless. In truth, it doesn’t really matter, but we’re humans, we’re curious, we want to know things.
IMHO: Knowledge for the sake of knowledge is never a bad thing (as long as no one is hurt in the process)