I've been a member of CEDIA for over 8 years and counting. They offer 3 levels of courses from beginner to advanced. When were you a member?
The OP is obviously just beginning in the industry. I was an AV hobbyist for decades before entering the custom home theater industry, worked in several construction trades, worked in educational/institutional AV for years, and designed and built my own home. The courses I've taken over the years have helped me greatly. Time I spent as an apprentice for a custom installation firm proved to me that there's a huge difference between what you learn as a hobbyist, versus what you have to know in the trenches.
There's a lot more to becoming proficient in custom home entertainment design and installation than theory, or pro AV applications. CEDIA classes aren't perfect, but the instructors volunteer their time because they care about elevating the quality of the industry. Many of the CES, Infocom, and EHX courses are taught by the same CEDIA instructors. Every student must take what they hear with a grain of salt.
I've been a member of SMPTE for over 4 years, plus taken classes at CES and from many other providers of all stripes. You have a right to your opinions but I still regard your blanket appraisal of CEDIA courses as shallow, elitist and ridiculous.