Do you have any idea how many man-hours go into the preparation of WWDC talks? Sure, other people may give away their development presentations. But then, they're not (IMHO, etc, etc) nearly as informative, polished, or well produced as standard WWDC fare.

Like seemingly everything related to Apple, if you don't perceive -- or just aren't interested in paying for -- the difference in quality, don't buy it. But also please at least consider not insulting the intelligence of those who do and are by claiming the cost isn't justifiable.