I listen to my mp-3 while running and walking. But I am ALWAYS aware of my surroundings. I'm wondering why they didn't feel the vibrations through thier feet?
It's a fair question. One consideration is that that these incidents are near to or inside of urban areas, where the trains basically idle along. Unless you're touching the rail, you might not know they're there. That's on purpose; they're running as quiet as possible.
But when they hit that main horn, they're pretty hard to miss. I suppose a fellow with a 12-ga. firing rubber bullets at the various grizzlies, moose, and earbudded-humans would be quite effective at preventing fatalities; though the optics would be universally lousy.
EDIT: Please note, I am not trying to be snarky or dismissive. One of these fatalities occurred a few minutes from where I live. It's a d@mn waste, and I sympathize with the family.