Morgan does this too. We tried everything mentioned in this thread and a couple more things, but nothing works. My vet said some dogs just do it, for no real reason, and will usually stop on their own eventually though some will do it for their entire life. This was after we tried everything and ruled out any health issues. We just pick it all up almost instantly so she doesn't get the chance. She actually is getting better about it though, so I'm hoping she'll completely stop soon. It's disgusting.