Dad mentioned that he could determine age by the number of keys a guy carries in his pocket - as he looked at my key ring. "The older you get - the less keys you carry".
More keys might me more responsibility; more stuff; less wealth to rely on other key holders; need for security; and the list goes on.
Kids love keys - just give one to an adolescent and watch their fascination. When you find a random key the first thing that pops in my mind is treasure - opening the treasure chest.Maybe Dad's quote makes sense. If you keep the treasure chest open, no one ever needs the key.