Mailroom aside, if a delivery guy is fine crossing a city with 20/30k people horizontally in traffic, I don't really see why this is such a bad thing when you break it down.
I count 35 floors, so you can cut it down to ~850 people on each floor after an elevator ride, and a building like this will probably have at least 4 elevator areas sectioning the building almost equally.
So you're down to about ~210 people after entering the right side of the building, that's like a big street / small neighborhood (and how far you have to walk should scale closely to that). And with this much people in one area you can really easily batch deliveries. And a delivery place will probably settle quite closely to such a hub of people anyways.
I agree with you, but if you measure the width of the dress at the tip of her fingers, the left and right are about 99-100 pixels, while the middle one is 105 pixels wide. Her face in all three images is about 38-39 pixels wide (measured at the earlobe), so that rules out they stretched the entire image slightly. But 5 pixels is significant enough to kind of muddy the validity of the OP's message since it no longer rules out all but the appearance of the dress. It sadly happens that sometimes effects are exaggerated, even when there is a real effect at play.