In some cases the RRB stop is more conveniently located for passengers than the station is, in which case why not. I noticed yetserday that there is a RRB stop for Kew Gardens station on the main road, right outside the main entrance to the Gardens, and not outside the station on the parallel street 200 yards away. This is probably more convenient for intending passengers, and also is less inconvenient for passengers not wanting Kew Gardens station as the end to end time of the RRB will be reduced.
However, the ideal arrangement was on our first trip to Austria. A schienenersatzverkehr(*) was in operation on the Innsbruck to Scharnitz route - the bus stuck to the main road but some of the stations were much higher up the mountainside, above the villages, and not accessible by anything as big as a bus. This was quite convenient for most passengers, but not for us, as the walk we planned to do started at Hochzirl station and went on up, and an additional 1000 foot climb at the beginning of the walk would not have been welcome - especially as it was pouring with rain, and we were running late as our flight had been delayed, and it was already mid-afternoon.
Without us having to ask, a taxi was waiting at Zirl for any passengers actually wanting Hochzirl station.
(*) translation hint - the word "ersatz" can be found in the middle of that word!
www.stagecoachbus.com
