Super secret hidden feature shown only to the faithful that showed up to Sears Point a few weeks ago...
Look at the handle of the charger. Notice that little hole that goes all the way through the handle? Minimally you can insert a cable or metal rod into that hole to lock it to something, though I'm not sure what kind of part to order to do that.
But, wait, there's more. Now press the button that releases the charger. Notice a little plastic piece that pokes into the hole (or tries to)? If you put the right sized cable or metal rod through that hole then they can no longer depress the button and detach the handle from the bike, thus locking the charger to the bike without having to have a long cable that loops around anything but the handle.
Still, it would require finding just the right kind of device that could fit through the hole, obstruct the button, and still be lockable. I'm imagining a metal rod that is the diameter of the hole, attached to a lock that goes around the cable with so little free play that a thief could not pull the rod far enough out to disengage the button without first detaching the lock from the cable...? Any thoughts?
All J1772 handles apparently have these hole/locks, but I haven't seen any devices that take advantage of them unfortunately...