It is the truck drivers responsibility to ensure that he operates his vehicle safely. This includes avoiding hazards in street like potholes, bicycles and children themselves. I find the original poster's comments outrageous. He tells us multiple times that these kids are supposedly non-english speakers and are muslim (as if any of that makes a whit of difference) and was too busy helping his friend with the move that involved the truck in question. Yet he had plenty of time to watch the incident and report it to us.
Had the bicycle been the poster's brand new LBS bike locked to a lamp post at the curb, I'll bet he would have been all over that truck driver's ass and on the phone with the company CEO.
The only right thing to have done would have been to go down and tell the truck driver that he had seen the incident and get his name and license number from the truck. He, or his friend, should have interceded on behalf of the kids to find out where they lived and reported the incident to the company that the friend hired to do the move.
The truck driver's actions were reprehensible. He bullied some kids so that they wouldn't report him. He knew he was at fault.