Dear Reb Eliezer,
My parents are not my esrog. I am not to treat them in some ritualistic manner, like a symbolic object. The wishes and the honor of my parents is the cheftza. The same with Yaakov and Rachel.
But the Leviim are part of the ritualistic act that is incumbent on all the Yidden to ensure it’s continuity. Just like the Beis Hamikdash is a cheftza, so too are the Leviim on their watch or platform. They could be defined as the cheftzah of being present within the required context.