Wait.....the 'COMPLETE' collection doesn't contain all of the expansions?!

Ok, so I'm a new player so forgive me if this is foolish but isn't it a bit strange that the most expensive bundle you can buy does not contain all of the content?

I even understand that it's supposed to be the 'Elder Dragon Saga' so I guess Secrets of the Obscure is just not part of that saga?

I feel a bit like 'old man yelling at cloud' but it's weird right?