Just to be clear, this isn't something the systemd developers came up with. ConsoleKit was responsible applying the same ACLs for local sessions before.
To give credit where it's due thoough I could me misremembering, but don't CK and systemd share the same developers? CK was their first go at session permission management - as of spring 2011 or so they deprecated CK and absorbed its functionality into systemd / logind.
gene/
