Auto signal as platform starter

[fil]

Hi everybody,
Im not sure if i am posting this in the correct place.

i came across an Auto signal at the end of a platform today. I wanted to know how these are used in this situation.
given the headway, the trains approaching the signal / station would be running on green aspects and the signaller would have no control over trains that need to stop at the station.
some trains would stop others would run straight through.

the only way i could think of is if the driver has intructions to stop, via route knowledge or WON?

are these a common occurance?
can they be used on any lines, or just infrequent rural line?
(layout permitting of course.)

thanks
fil