It's totally normal, our 5yr old still does this with her rawhide chewies. She hides them in our closet under the dirty clothes or in my daughters pile of dress up clothes in her room or under the kids pillows. He is just hiding them and he is using his nose to cover them up the same as he would do outside if he dug a hole to bury his greenie in then he would have to put the dirt back on top. Just leave it where he puts it and he will go back and get it if he wants it
