I believe Mr. Nicklaus is doing the design work at the Scarlet course for free. But a lot of the "free" deals you hear about are not really free. Pete Dye has donated his time for free on several projects, but his associates are paid what would sound like a decent architectural fee on those jobs.
I have done a fair amount of free consulting in my days; The Confidential Guide even had some unsolicited suggestions. And I'm looking into some alternate forms of payment on some projects which can't afford our escalating fees.
However, it is pretty difficult to draw the line on fees for new golf courses ... if you're going to do one job pro bono, how do you explain that to the rest of your clients? They all require a few million dollars to get built, so the architect reducing his fee to nothing is not often going to be the difference in getting a course started. But, I will consider getting paid later in the game, if I really trust the client.
There are probably plenty of young architects who would be willing to work for free to do a project on Pacific Dunes - type land, and in the long run it would be worth it to them. But I would advise them against it. Designing a truly great course is going to create a lot of revenues for someone down the road, so it's only right for the designer to be paid fairly. Fortunately, most of the people who are smart enough to shop around for great land also understand that you get what you pay for, and are well enough off that they don't need to take advantage of a young golf architect.