Brian,
Do the upper end gca's drive those specs, or the PGA Tour or CC golfers who want ever better and more consistent conditions? Here is a list of "standard" high end specs off the top of my head:
USGA Tees (so they can be level rather than slope 1%)
Sand Cap FW (often accompanied by Zoysia sod)
Other Spec topsoil mixes for fw (PGA Tour has some real strict particle sizes requiring screening)
Sand Cap Approaches for firm and fast run ups
Herringbone Tile in approaches to dry them out
Sand Cap chipping areas for more reliable bump and run from chipping areas
Bunker Liners and White Sand (imported at nearly $100 per ton in many cases)
The pure quantity of bunkers (well over $100,000 SF for some designers vs 50K SF for others)
USGA fairways and herrigbone tiles (less common but out there) for drainage consistency
Learning Centers (vs driving ranges, even though 99% of golfers only bang balls to warm up)
Sib-Air Systems to Cool Greens (often to push bent grass further south than it ought to be planted for greens)
Fans to cool greens (often to push bent grass further south than it ought to be planted for greens)
In irrigation, we have:
Part to part green heads
Part to part fw/rough heads,
Part circle heads on the edge of turf to avoid spraying into natives,
Small heads on tees to keep native look around tees, etc., etc. etc.
The biggest cost offender is 3500 GPM pump stations and the trend to shorter water windows, so that watering ends early and maintenance crews can get out and be off the course before the first tee time. In general, I see courses that need 200 acre feet of irrigation a year, or an average of about 400,000 Gallons a night, but somehow, they get systems designed to push out over a million gallons. I know there are times when a system needs more than average capacity, but I wonder how much when water restrictions will never let them use that much. It's all because irrigation designers and supers are afraid that there may be a few nights a year where they will have to extend watering past the normal cycle, or let the turf dry out a bit.
So, perhaps we are a bit OT here, but those specs, as Brian notes, are what has been driving the cost of golf up. Now, there is nothing on that list that I wouldn't want to have, at least on certain sites, and especially the sand and draingage to keep certain areas dry (although a reduced irrigation system would also generally help there) And, to some degree, spending the money up front reduces future capital and maintenance expenses and is a good investment.
I am not sure any designer is as responsible for that as is the generally rising tide of maintenance standards that golfers expect.