I can't ever recall being told to specifically put water on the 18th hole. I have had routings affected by a clients desire to have a good view of the 18th for "when they play tournaments" there, avoiding the delicate question of exactly which tournament they hope to secure (We're nowhere near Tuscon, AZ, but I think they need a new location for the Tuscon Open!)
For that matter, most of my heavily watered courses are because we needed to connect lakes to provide drainage outlets on flat sites. I would think you could appeal to their fiscal conservatism, showing the cost of building and the evaporation losses, etc. When put in terms of gallons a day per acre, most people get quite alarmed.
Just as someone opined about repeating the early American mistakes of large clubhouses over there, I guess they seem doomed in China to repeat some of our later mistakes, too! (i.e., 1950's lake building era, just because we could)