Having read the above posts and talked with and emailed several shooters outside the forum, I’ve got new insight on the subject of post #1, as discussed below.
As for score shooters in my general part of the country: first, there appears to be a match most every weekend during the shooting season that is within “reasonable” driving distances and many of the shooters may not have much time (or motivation) left for shooting unregistered matches; second, the points chase is a BIG draw, even for those shooters who don’t have a realistic chance of winning SOY; and third, they are like “family and it’s like having a family reunion most every weekend.
As for group shooters in my general part of the country, the only things I can see are: one, they don't trust their fellow shooters with the absence of a moving backer; and two registered matches just create more "buzz" than do club matches -- for example, the opportunity to: (a) shoot with several (or many) celebrity-type shooters; (b) enjoy the "family reunion" aspect mentioned above; and (c) be part of a "happening."
For now, I'm thinking I may have answered my question; however, feel free to share other ideas.