This is an accounting question, no one intrinsically cares about identities except as entertainment or for sentimental reasons. If someone said that we Officia

This is an accounting question, no one intrinsically cares about identities except as entertainment or for sentimental reasons. If someone said that we Officially (TM) become a different person when we sleep and wake up, no one would care. On the other hand, we would really care about cloning because all sorts of things assume it to be impossible and it would all be a huge mess in practice. Not because the identities got tangled, but because as a consequence we don't know how to jail someone who created a clone a year ago, for example.