Thats incorrect on two accounts. The first is that clients are not getting more educated, they hire freelancers because they don't know anything about websites and really don't care to. While many may know of wordpress, it doesn't mean they know how to use it. The second is that wordpress and joomla are plug and play solutions for the majority of problems; they are not. Even when using a CMS a lot of custom programing often needs to be done. Sometimes working with the CMS can actually make the task take longer or be more complex so it is not always done.

Perhaps you are somewhat mistaken as to what type of custom programming jobs normally go around. I've never coded a blog because such a job has never came to me (they all use wordpress or another script), I've never made a news website because they all use Drupal or another CMS. A few of my 100% custom jobs have been a directory script with some very specific functionality, a flight logging site and a secure messaging system that allow users to exchange files (mostly confidential stuff).