THey'd probably rather knock your door down than waste their precious time trying to give it to a neighbour or worse still having to call back and put themselves out of sequence.

On the subject of amazon deliveries my wife only fairly recently discovered the pleasure of on line shopping and being able to send things back (all new to her for a particular reason) and it seemed like there was an amazon man knockin on our door every day.
I made a joke of it in the pub one day saying the amazon man knocked and when I opened the door he said he didn't have anything for us. When I asked him why he'd knocked he said "Force of habit!"