"So you made my point - locals might play CS once a year and other Scots aren't about to pay the higher rate so the vast majority of players are from outside of Scotland."
Jerry K. -
I am not so sure about that. You will note Jon W. said "at least once a year," not only once a year.
I have no way of knowing for sure, but my guess is the number of rounds played each year at Castle Stuart by residents of the greater Inverness area and SGU might surprise you. While the "majority" of the people playing CS are visitors to Scotland, my sense is a healthy minority are not.
Frankly, I do not accept the notion that the native Scots are not willing to pay up for an occasional "special" golf experience that is different from their home clubs. Some of the most enthusiastic fans of Castle Stuart I have met over the years are the locals. Given that many Scots have watched the Scottish Open played at CS multiple times on TV, it is not far fetched to guess that many of them have an interest in playing the course.
On a different note, it is worth noting that the traffic across the Atlantic to play golf is by no means a one way street these days. There are a sizable number of folks from Scotland (and elsewhere in the UK) who travel to North America for a golf holiday and are willing to pay a premium to do so. I have met a number of Scots who have played a wider variety of golf courses in the U.S. than I have.
DT