You know how when you give a child a gift they would rather play with the box than the toy? Well the same applies to puppies.
My puppy’s favorite toys are common things that I don’t have to buy. Her very favorite is a cap off of a water bottle or milk jug. She will toss it around and play fetch. When she has “killed” it she starts to chew on it. At that point it gets thrown away.
Another favorite is cardboard boxes and paper towel tubes. My pup loves to lay and play in a cardboard flat. Old socks and towels are fun for them to shake and play tug of war with. Pups love shoes so why not give them one they can chew on.
Mother dogs give their puppies things to play with which explains why a pup will ignore a toy she already has until you go and pick it up. Whenever I empty a box or find something puppy safe I give it to her. Letting puppies play with a variety of items also helps with their development. They need to discover all kinds of objects so they won’t be afraid of new things in the future.