I have noticed that in some of the episodes that shoes have been carefully placed or inserted. For example, in the pilot, in the very beginning as Jack is running to the beach, he runs past a white sneaker in a tree. Then later, they had the significance that Kate wasn't wearing "proper" shoes, and took a pair off the body. In White Rabbit, Locke's shoe is off when he notices he can move his foot. Then in some of the chat rooms, people have been saying that there was some significance to the white sneaker's that Jack's dad was wearing. Anyways, my question is:

Is there any significance, or symbolism, to shoes?

I'm not looking for spoilers or anything, I am just wondering if they are important or if they are just part of background and costumes. Thanks for a great show, I am completely addicted.

To paraphrase Freud...

Sometimes a shoe is just a shoe.