Okay, I didn't even know about Royal troon, Sedgefield and Birkdale until you guys mentioned them. So, this is interesting, I do have those in my "Courses Folder", but they don't show up in the carusel. Also, on the "PP Social Site", their not available for sale. I can play all the ones showing for purchase. Since Jurgie said the purchase buttons don't work, sounds like PP unlocked these intentionally for us. For the other 3, they're may have been some rights violations or something, and they couldn't unlock them.
Also, for you guys that aren't seeing these, keep in mind this was a fresh download of the game. Here's a pic from the course purchase page.