It sounds like he is talking about a car accident. I probably think this because of the highway refferences.
"Every sort of person looked like hell
With their hands in their pockets
And the marks on their scalp"
Everyone looked like they've been through hell. The marks on their scalps might be injuries.
"I couldn't breathe under all of that weight, and the things that we've seen.
With all the dead, with their hats on their chest, and their thoughts in the leaves."
The weight of what he saw pushes on him. The things he has seen are dead bodies with their "thoughts" (aka brains) on the side of the road.
It sounds like he is talking about a car accident. I probably think this because of the highway refferences.
"Every sort of person looked like hell With their hands in their pockets And the marks on their scalp"
Everyone looked like they've been through hell. The marks on their scalps might be injuries.
"I couldn't breathe under all of that weight, and the things that we've seen. With all the dead, with their hats on their chest, and their thoughts in the leaves."
The weight of what he saw pushes on him. The things he has seen are dead bodies with their "thoughts" (aka brains) on the side of the road.
...just my 2 cents