I should have read this post first before calling Samsung Support. I called them and they told me it is not normal that I should go ahead and return the phone since I am still within the 15 day period. But the reality is that any thing that shakes or clicks like this will cause premature wear and IMO with something as sensitive as the camera is, at some point it will degrade the performance.
Had I read these post then I might not have returned the phone. But it really shouldn't rattle when the camera is not selected. But open the camera and the rattle definately goes away. Maybe the solution is to keep the camera app running in the background.
I KNOW WHY, The 10x zoom feature uses a mechanical slider to operate. When the camera is not engaged, you will be able to hear this, If you are on the camera app, zoom in, and you will not be able to hear this, if you can still hear it after zooming in and shaking, you will probably notice that your zoom is having a spazam.