Well I will watch them. Because although it may not be the ideal way to learn, if it teaches me one thing I didn't know then what harm has it done.
Many folks are not geared toward class rooms or text books, for some a youtube vid they can watch over and over and skip back and forth is easier to digest than other forms of media.
Personally speaking I love to learn, love to read and enjoyed my education but I know many many people who grow and are at the other end of the spectrum as far as their ability to take in info from text or even their ability to attend classes either through physical aliment or lack of social skills.
Its another form of media that can be useful to people, where's the harm in that.