Advertising isn't simply manipulation. Advertising also serves the purpose of distributing information about products, services or ideas that people otherwise wouldn't ever know about. Isn't that one of the big issues people always bring up here? Distribution of information? Sure, it's slanted, but what human-generated information isn't? It's all presented based on our perceptions and intended purposes. At least when the info comes from advertising, we know it's slanted so we know to look into it further.
There are always exceptions to the rule; they don't disprove the general usefulness of paying people to promote products, services or ideas. Even various Linux distros use some forms of marketing, such as selling branded items like hats, shirts, etc. Traditional advertising isn't the only way to market something.
Anyhow, just because some people choose to purposely avoid heavily advertised products, it doesn't mean the advertising is worthless. Those companies that can afford to burn their messages into your head obviously get those billions they spend on advertising from somewhere, and they wouldn't have gotten where they are without it.
I'm not trying to start an argument. Just pointing out that there are different ways of looking at things, there is a valid and important purpose to advertising and marketing, and people in marketing aren't necessarily stupid just because most don't understand "technical stuff".