Advertising's Critics and Supporters

What are the three main arguments given by advertising’s critics and by its supporters?

Advertising critics argue three main points: advertising adds to the cost of products, advertising causes people to buy products they do not need, and advertising reduces completion and thereby fosters monopolies.  The cost associated to the products do in fact relate to the overall cost the consumer pays when buying the advertised product; however some products would not sell as well in no one was aware the product existed.  Advertising sometimes persuades people to buy things they do not need, but it is up to the consumer to make necessary purchases.  Supporters of advertising state that ads helps pay for media in newspapers, magazines, radio ads, internet, and the television.