Leaf spring leaves not centered

While I had my rear end jacked up and off the ground so I could try and find out if my axles are bent, I noticed that one of the leaves on my p/s leaf spring was not centered with the rest of them.

I checked the other side and they weren't exactly straight, but not as severe as the other side. What could cause this? U bolts too loose?

And while checking the wheel bearings (checking for movement in the tire with hands at 12 and 6) I could see some movement between the spring leaves. I have it jacked up on the frame so the rear end is hanging loose...I was thinking this might be why?

Any ideas?