They don't seek to inform you so much as they seek to inform you that something exists whilst manipulating your emotions to get a particular reaction out of you and millions of other people. This is particularly blatant in AV ads.

The other thing, mainly regarding software ads, is they don't seek to inform you so much as manipulate you whilst tracking your every move to guarantee that the ad was effective. This is particularly blatant with the Google and Facebook ad networks, but pretty much almost any 2-bit ad company you've heard of on the web at least tries to do something similar.

So in the end, advertising has at least two major problems with trying to either 1. manipulate you directly through your emotions or 2. manipulating your computer bandwidth and CPU time to violate your privacy and oftentimes, security.

Regarding #1, there are always going to be people that think they're smart enough, intelligent enough, or logical enough that they will never fall prey to this vector of advertising, and almost universally they are wrong. I don't doubt some few exceptions exist, I just don't think I've ever actually met someone who is an exception, nor am I under any illusions that I am. Your best defense is to cut ads out of your life to greatest extent possible. You'll probably never cut bus ads out of your life, if you at all enjoy city living, but you don't have to let advertisers into your home either.

How do you find out about things after that point? If you are at all social, read any kinds of news sites, invest any money into markets, have any kind of skin in some kind of game, or engage in any kind of recreational activities, you'll have other channels of information. Generally the signal will be of a much higher quality than if you were personally bombarded with advertisements intentionally seeking to cut out a large slice of your overall attention bandwidth every single day.