A few points....
Is it so foolish that a police officer could have been wrong? He could have spoken up, not understanding what was actually happening.
A mob of people killing each other over a car? Have you seen a mob? My brother was in *our* car on Canada Day downtown, and a mob of people, who are apparently harmless, trampled over it, with two of our friends inside it, and destroyed the vehicle, caved in the roof, shattered all the windows, and crushed the hood and trunk. Again, this was *with* people in the car at the time, while it was moving. Mobs are not harmless, and in groups, people are irrational and dangerous. When they tried to get out and pull people off the car, they almost got the stuffing beaten out of them.
The movie wasn't perfect.....but some of the things, like aliens not having bio suits, falling victim to disease, etc.....that's part of the book. It's the whole point.
I was wondering about the van. That's a pretty efficient motor. But I missed the beginning of the movie, so I'm not sure what city they were in to start with, or how far they actually drove.
Banshee