Did these people forget that operating a motor vehicle is a responsibility and privilege, not an unlimited right, that their behavior has consequences for the general public (externalities like air pollution, collisions), and that they are required to follow the law when operating their vehicle?
If the city cracks down in idling then either Amazon will relax the targets or nobody will fulfill them.
There might also be mechanical reasons. First, according to what I've read stopping and then starting puts more overall wear on the vehicle than idling unless we are talking about a long time between the stop and start.
Second, if they are going to spend all day alternating between short delivery stops and short drives to the next delivery they might have to worry about whether or not the battery would be able to handle all those starts. The short drives might not be enough to replenish the energy from the battery that was used for the start.
The consequences you mention, feel more like a consequence of us demanding X amount of goods in our cities each day, and having no other infrastructure to get them there besides trucks, than the drivers individual malfeasance.
Responsability yes, but a privilege?
If public transport were abundant and pervasive everywhere in the world that would be true. Freedom of movement is a basic right and in a lot of places, you can not enjoy that right unless you have a car.
Most of the people were born with a pair of legs, which they can use to enjoy their natural freedom. A car is still a privilege for those, even if economics “require” them to own one.
So ... they're just like 90% of the posters in any HN thread where driving in excess of the speed limit on the highway is discussed then?