In other words, the documentaries and lectures that we are watching are ALSO trying to communicate information in a convincing and informative way. They are not trying to sell a product, but they are providing information about products and perceived value. Eventually YOU will be asked to prepare a short speech on a topic that you are passionate about. You will be required to use all the knowledge you have gained during the unit about perception and effective communication to get your message across to your classmates.
With that in mind, watch the following TED lecture http://www.ted.com/talks/lang/eng/rory_sutherland_life_lessons_from_an_ad_man.html about advertising and perception through history, and respond in the "comments" section above with some thoughts and feedback about what Roy Sutherland (the ad-man) has to say about value in our society.