An email address can be quite long, enough to pass off as a poem or other form of art which can be copyrighted.
Apple is doing the same with an encryption key embedded in Mac’s SMC chips. The key is something like “our hard work by these words guarded, please do not steal (c) Apple Computer Inc” and is used to decrypt system binaries.
While providing no actual security I guess it gives them a leg to stand on should anyone recreate a machine capable of running MacOS (the OS would not start without this key being in the hardware).