That's how I've always imagined it. The top of the FedEx truck is a mini-helipad, and there are two people on the truck. As the truck makes its normal route stopping to deliver heavy packages on foot, there are two drones darting back and forth delivering light ones, with someone constantly feeding them packages and batteries.
Somewhere years ago I have a chat log where I describe the whole thing as imagined, including the phrase "print out helipad_qr.pdf and tape it to your driveway" as part of the process. ;)
