Fed Ex, UPS and other companies who do residential delivery all share in the problem.
Best bet for the delivery employees is for their employers to REFUSE to do "to the door delivery" anymore ~ and not just in Wisconsin, but everywhere.
This interpretation of the Stand Your Ground concept certainly justifies widespread installation of Cluster Boxes all over America.
No sense taking the risk that some guy just doesn't recognize the carrier and decides to shoot him.
Legal gun owners are a responsible group and they do not take that responsibility lightly. No one is protected from prosecution for recklessly hauling off and shooting a person who sets foot on their property.
And for that matter, there are places in Milwaukee where the likelihood of getting shot during daytime hours is increased and it's not because of concealed carry or the castle doctrine.