True, but I'm guessing this is aimed at small companies without the resources to do their own CA. To you and me it's not that hard to do, but I can think of several small business owners I know that wouldn't have the slightest idea.
Many small businesses don't have the resources to wash their own windows, or change the oil in their vehicles. So they pay someone else to do it for them.
IT in all its guises is no different - it's just that many businesses think that getting a favourite nephew in to do the job is a viable approach...