I don't know the Gordon Kaye story, but "those people" that get involved for search and rescue operations are usually professionals who would, in fact, spend that time working to help other people instead.
In some cases I believe you're right, tradeoffs do happen. In other cases they are just on call. This is why private rescues are so expensive. You aren't just paying for the professionals and the equipment, you're paying for them to sit around until called.
Yes. You might say that even if they are just sitting around, their presence doing so is considered to be a valuable part of their job, and it is being wasted.