Yes, SC = Staus Credits.
For some the only reason to travel is to get to the destination, but for others, a relatively cheap flight to Fiji and back, via a few key cities, could earn you status that you could then use when you actually go on holiday, or on business. In ways such as getting to use a First class lounge that you otherwise wouldn’t have had access to, or a better change for both paid and free upgrades. Or even just better seats on the plane.
Compare a paid First fare, giving you First lounge access and First seat, to say a Business fare, not giving you First lounge access and a Business seat, but if you have the points and the status, you might get that upgrade to First and you can get into the First lounge, for a lot less…
Or simply flying Economy and getting to sip Champagne for a few hours before your flight, instead of sitting next to the gate in an uncomfortable chair.