The trains must have to travel at a very low speed to allow such a system to work. A train needs quite a good distance to brake. It is not going to work well if passengers have to walk a good distance down the tracks to catch up with where it stops. I suppose it only really works with very low speed branch lines where the train can brake quickly.
I got the train from Abchorage to Fairbanks some time ago.
I wouldn't call it a branch line, though we only passed one train in the whole time.
It was in October, at which point the Winter service of one train a week ran.
The train consisted of a locomotive, baggage car, and single coach (I think the summer they get a bit longer)
Catering was a fridge with sandwiches in and a margarine pot on top with a slot in to put your money through.
I don't think there were many other tourists on it.
As it was northbound, people were getting off in the middle of nowhere rather than on.
The whole thing was quite an experience - the conductor came down with a notepad and people told him the milepost they wanted.
Then at the stops people got off with their supplies from the baggage car - and some had quite a lot of stuff - big boxes, timber, gas cylinder, barrels, crates of beer, dogs.... all handed down to track level.
The stops seemed to be in the middle of nowhere - not even a sign of a trail going into the woods.
Two people got off at a river bridge with an inflatable dinghy.
I don't know what happened going south the next day to pick people up (I flew back - also interesting in a mixed passenger and cargo 737).
Perhaps they knew to stop at the places they dropped people off at?
I have never done anything else like it.
Edited:
Actually having dug out my photos I see that in fact the catering was more elaborate than I remembered. There was also a table with a hot water urn and things to make yourself a hot drink with.
