The top photo shows a crash landing at a relatively low speed . The bottom photo shows the crash site of United Flight 93 which nosed dived into the ground at 500+ mph. Big difference. Basically, the higher the speed and the steeper the angle at impact, the lesser the amount of wreckage left.
What's really interesting about Flight 93 was that pieces of the aircraft were found in a miles long trail before the crash site. This would indicate that it was shot down, but you won't hear that on the TV news.