At the time they couldn't do the kind of microsurgery that's necessary to re-attach tiny blood vessels. So if they cut a piece of skin and sewed it on somewhere else, it wouldn't have a blood supply and would die. They left the transplant part attached to some part of its original blood supply long enough for it to heal to the new place.
I feel kinda bad for that one poor fellow that's going to have a nipple where his ear should be...