What's to stop someone from stealing a Mac, and on the first boot putting an install disc in and completely wiping the operating system?
If someone did that it would have no ties to anyone's iCloud and wouldn't be trackable or controllable.
Just saying, none of these services really protect you.
Usually these great bits of software come with a locking service, you lose the Mac? Lock it, stop installs, formats and nearly every other bypassable method.