That isn't the same as "employing someone just to keep them busy", though. They are employing them to make more money; it just so happens that the work they are

That isn't the same as "employing someone just to keep them busy", though. They are employing them to make more money; it just so happens that the work they are doing doesn't actually provide value to society. It might seem like a minor distinction, but I think it matters when trying to understand the motivations involved.