From Brian F:
The image you posted doesn’t really show how ridiculous this only one is acting. Take a look at this one from a different angle. If the driver is so menacing, why does the only one in the background look like he is ready to fall asleep?
Maybe he's walking over, but you're right--he certainly doesn't look prepared to be in an area where such a police reaction is justified. The thing is, it's not the first time we've run into the phenomenon of threatening citizens with lethal force while others stand around with their thumbs up their...uh...their hands in their pockets.