I think most people these days take scalability to mean the ability to handle more load by adding hardware without changing the architecture. That's quite different from how much load the same hardware can handle (performance).
I dunno, I hear the term "scalable" applied to business decisions all the time. I think it encompasses more than "Is this problem embarrassingly parallelizable?"
In business terms, what people usually seem to mean is "able to bring in more revenue without having to hire people with skill sets that are rare or difficult to qualify". A software consulting business doesn't scale because it requires hiring programmers; a telephone support business might because it's much easier to hire people who can speak English and follow a script.