That demon is the "shrine".
Also those stones are starting to give me bad vibes, what if they drain the life force or something?
Just seems like a very suspicious tactic, giving something an arbitrarily high price in order to increase its perceived value and desirability and then lowering the price is a common sales tactic. This way people that would otherwise not have, will now happily take these stones for free.
He doesn't seem like the super altruistic person that just wants to protect people, but this tactic could line up with such ideals.