Well, BKKROP you have a point. If somebody is willing to pay the high prices for hotel rooms at the Raffles, then the $120 cost for the day for driver/guide should come with the territory. And I'm sure that doesn't include the cost of the passes per person, that's just for vehicle, driver and guide.
I do take issue with the insinuation that "properly" means paying as much as possible. There are many ways to get a reputable driver/guide and do the temples "properly" as you put it, paying 1/3 of 1/2 of the asking price of the Raffles concierge. It just takes a bit more homework to set up. As well all know, a huge part of the cost is in the hotel markup, pure profit for them, since the effort involved in setting up the guide/driver is a <5 minute phone call. Is the Raffles experience worth 2-3 times as much as that with an independent? Well, I sort of doubt it, but whatever people want to believe....