Thanks for the comments Tom, to be honest I'm not sure why.
I found the old boot laying in an old quarry a couple of years ago and its sat in the car since waiting for an oppertunity to be used once again.
I thought the boot had a certain character, a sort of lived in look to it to it. And I suppose in a way the robin has learned to live and become very friendly with mankind. So I guess its a harmony thing going on there with man and animal ie peace and harmony.