Most golf architects I know fight budget increases for golf all the time, and then sit back and watch clubhouse budgets spiral out of control. We argue that its golf that brings them in, often to no avail.
Most clubs would need no more than 10-12K SF, and could probably get by with a little less. Public courses can get by with 6K SF or a little less. Have seen them built at 4500 SF, but never have enough office or storage. And, ADA laws mean you can't legally use attic for storage, as it might affect the civil rights of a person confined to a wheel chair, who couldn't perform a job there that involved going upstairs, at least without building a $50K elevator......
How many 25-40K SF monstrosities do we see sit empty most of the year? A lot, but its always a different entity making the same mistake.