It's a universal safety sign made to have uniform safety requirements at railroad passenger stations. There might be a station that is an end terminal or certain conditions that may make the sign obsolete, but on the line stations that would see more traffic density, it would make more sense. Even completely seperated transit must (well, depending on the State's requirements) indicate that some trains will not slow down or stop. If the passenger transport runs only a portion of the day, most trains will run empty to a secure location to be stored. This might also be the need to have the signs. What would happen if there were no indications of unique train movements? What would you think if you drove to the next town and the traffic lights were blue and orange? Like I sad at the beginning of this rant, It's a universal sign.

This "observant" foamer really does not know the rules that railroads operate on.