Okay, 20 feet away with numerous people standing at a bus stop directly in front of the collision - can't see? Collision occurring practically beside you... Still can't see? I was close enough that the back windshield and passenger rear window showered my car with broken glass.
According to you, I should have just driven by like everyone else, placed a call, and been on my way?
What did I do? Placed the call, driver was obviously in a panic and left his car running while attending to his kid in the backseat - switched off his car. Upon impact, the rear end of his car was completely gone, his trunk was squished into the back seat popping the seat up and forcing the kid in a forward leaning position.
Should I have assumed that the dad was trained in first aid? Was given basic instructions from the dispatcher of what should be done to aid the kid and passed it on to the dad.
Lets drive off and not give a witness statement either and been on my way - should we do the same for hit-and-run motorcyclists? "Damn, that rider got hit pretty good, but it's none of my business, so I'll just call 911 and he/she can lay in the ditch and wait"
Lets use your avatar pic as a reference. What if nobody stopped for the fallen rider that passed and just left it alone? Would that have made things better or worse?