"So why these folks?"
The families of the civilians who were killed on9/11 were compensated in this manner for one reason only - to avoid lenghty litigation that, it was feared, would bankrupt the airlines and other companies involved. Not to mention that such lawsuits might have dragged on for decades and would have left many people without any compensation at all for their loss.
Like this concept or not, that's what it was. It was in no way intended as any kind of "reward" or "jackpot" for those involved. Police and firemen already have systems in place to compensate their families if they die in the line of duty, that is a different situation, although I imagine the FDNY's system was severly strained by so many deaths at one time, not to mention the increase in retirements afterward.
The compensation that many of the 9/11 relatives got was outlandish; I feel for them and their deceased relatives but they got far, far more than the families of our veterans killed fighting for this country in Iraq and Afghanistan (some of whom were on their third combat tours). Nonetheless, some of the endlessly-complaining relatives of the 9/11 civilian victims (I exempt the fire, police and rescue personnel who volunteered to save them and whose relatives always seem to bear this with grace and dignity) have the nerve to complain that the taxpayer-funded jackpot isn't enough! Compare it also to what the families in Oklahoma City, Khobar Towers, Somalia, and the COLE received.