True. Even if you presigned, it's ultimately the driver's call. And a lot of them won't leave a package that obviously contains pricey items on the front porch for anyone to take. Can't really blame them : while getting the dreaded sticker is a pain, having their package stolen would make people way more angry, and probably accusing UPS/FedEx too.
If you can, either ask for the package to be left somewhere safe, or, better yet, arrange for it to be delivered to a neighbour.
I'll arrange for it to be left with my building's office staff, but even then, it's hit or miss...