It's all true
Depressing, huh.
I think the main point is that it is possible to sell ethically - provide the buyer with information, explain things they do not understand, and generally assist/guide them in making their choice. A choice that is right for them. PC World sell on the basis of what must be sold (becase it's end of line) or what will earn the most commission. And they do this by exploiting the customer's lack of knowledge.