It is H&S gone mad.
Chessington Train Station does not have any barriers, or stops people going on the platform before the train arrives.
The car park does not have to be shut every time someone gets out a car, so they can get the the path safely before another car enters.
Its common sense, and sensible parental supervision. Why does any roller coaster station need a barrier really?
If your messing about on a train station, and fall on to the tracks, its your fault. It not the rail operators fault, its not the governments fault, it no one's fault but your own, or the person responsible for you. This may seem a little harsh, but the same should apply in a theme park.
Now, if the path was cracked, or the floor surface was uneven, due to poor maintenance, then that is fair enough, and you should be able to take action.
Lots of ifs and buts, but in general, if your sensible, and not messing around, there is not much harm you can do to your self in a rollercoaster train station.
Ian