I would think it refers to the drivers.

People who drive under the influence of drugs or alcohol don't think that they might die. "Nothing'll happen to me" "I'll be fine"

It is the same psycological effect kids have in extreme sports. They don't believe they will die - without actually saying the words to themselves - they know they are immortal.

Do we have any psychologists on board. I'm sure they could explain it better than me.