Answer:
Everyone has me except for a few. You may not be able to identify me but I can always identify you. What am I?
Flat as a leaf round as a ring. I have two eyes but can't see a thing.
The more you take the more you leave behind. What are they?
Weight in my belly trees on my back nails in my ribs feet I do lack.
When young, I am sweet in the sun. When middle-aged, I make you gay. When old, I am valued more than ever. What am I?
They are many and one, they wave and they drum, Used to cover a state, they go with you everywhere.