Dude I think this is procedure now.
I find packages on my front door step ALL THE TIME now.
My front step is literally like 8 feet away from the sidewalk. Someone could easily take my package and keep walking.
I fear this. But like the dumb @ that I am, I have not done anything about it. Except post this.
Edit: Actually after re-reading your post. My post is actually irrelevant. The big name delivery services could be knocking my door, but maybe my wife is banging it, and that's why packages just end up on the door step.
Double Edit: Maybe she's banging it with the ups/fed ex guys/and dhl guys. She wouldnt mess with the usps guys.