That's the point. You don't trust anything, commercial or not, by default, you use your critical faculties and evaluate the information available to you to reach a conclusion. As such, advertising isn't special, and isn't inherently evil anymore than any other type of communication.
My comment above. I assume yours as well. Most of the internet, actually (e.g. HN, Reddit, ...) - the owners of the website might benefit (pageviews & ads), but not the most often anonymous posters. (Of course, there are exceptions, and any post on the internet should go through a bullshit sensor, but it's a different bullshit sensor than when someone is trying to sell you something.
my communication was a challenge to you, to promote my worldview (laissez faire free market) to the 3rd party readers of our exchange. Since my skills, knowledge, are heavily intertwined with this worldview, my value goes up when people sway to this worldview. So in pushing this agenda, I profit.
Let's say our posts were purely entertainment value only. I still profit because I am entertaining myself for cheaper than the alternatives, saving money, and therefor profiting.
Usually we call people who take action that don't benefit themselves crazy or self-destructive.
I totally agree that all communication has a goal/motive; I was referring specifically to advertising/for-monetary-profit communication, mainly because such communication in itself is an indication that the originating party is driven by profit (they are willing to lose money for the chance of convincing you), not by altruism (such as e.g. reading these comments on HN or reading fitness advice on reddit).
This also the problem with paid advice (lawyers, fitness trainers, therapists, ...), as the incentives are rarely aligned - the better the service (faster resolution of the problem), the more the customer benefits, and the less the seller earns. Hence, sellers are incentivized to not offer perfect service. Of course, market efficiency is high enough that those who offer really bad service (solve the problems too slowly or not at all) will get a bad reputation, but it's reasonable to believe that the optimum for each individual seller (and hence for the market itself) is less-than-perfect-service offered to customers. This is obvious even in fields that are highly regulated, e.g. medicine: most drug research is targeted to managing long-term diseases (HIV, cancer), so that the customer stays a customer as long as possible; one-shot medicine (e.g. for snake bites) are "priced out".
It's even worse in politics; politicians can promise anything, get elected, do the opposite, and blame the opposition.
On the other hand, the incentives online are different. There is no money, only reputation, good feelings (altruism) and lulz. Therefore, you need a "bullshit-test" to filter out the trolls (e.g. upvoting, reputable peer-reviewed blogs), but if you do that successfully, the incentives of producers and consumers of information are aligned.
Finally, this is only my thinking and analysis of the state of the world; I might be wrong, and I encourage you to point out any errors in my thinking and change my mind.
Your thinking is well reasoned. However, I think you are defining profit too narrowly to a direct currency transaction. Money <> Time <> Happiness are fungible to a large degree. Even altruistic actions are done for profit. I received more satisfaction and sense of well being from building a Habit for Humanity all day than I do from a $500 prostitute. My point is that people who don't profit (monetarily) from communication are not 'good' or morally better than people who do. Your politician example is a great example. Their effective communication definitely increases their future profits (govt employment, lobbying, or political donations) because it increases their political power. You could say that Brand advertising has the same profit timeline as political speech.
I don't think there are many differences between online and off. Main differences are anonymity and scale. The drivers of behavior and dynamics are pretty much the same.
Not profit in a strict monetary sense, but you benefit in various direct and indirect ways from advancing your worldview and challenging mine.
I see the focus on monetary profit as somehow 'dirty' at the expense of the myriad other ways people benefit from interactions as a further symptom of the snobbery described in the link I posted.
