That's what I was wondering.
It's not like trains sneak up on you.
Many years ago I was walking with my son on the Air Force Academy alongside a set of rail tracks. At one point I turned around nearly jumped out of my shoes, there was a coal train 30 feet behind us moving towards us at about 20 miles an hour. It was almost noiseless.
You couldn’t be more wrong. You cannot year or see a train until it is almost on top of you if you are distracted. I take trains and cross numerous crossings on foot every day, and you’d be surprised how soon a train can be right next to you without knowing it unless you are paying attention.
They do if you ware listening to music.
Freight cars that have been pushed into a switch yard can surely sneak up on you. Locomotives, well that is difficult to imagine give that the ground shakes right along with all of the other racket.