Advertising, like the ads you see around you on this blog, pay for a free service like blogger. Google isn't providing this as a public service, nor is it paid for by in some mysterious way. It's driven by advertising. And advertisers will pay a lot of money to attract an audience, like you, to see their ads.
But if advertising is driving you to distraction, there is a way to avoid it. Avoid free services. If you're watching, for instance, The Three Stooges on YouTube, you are obliged to see ads all of the time, even if it means just waiting five seconds to skip them. To avoid this, pay for The Three Stooges yourself. I found them on iTunes, and I can watch them as much as I want, with no commercials. Yes, it cost me $19.99.
It comes down to this: if you're naive enough to think that stuff should be free, you are exactly the kind of person that advertising is directed at. And in the long run, it makes you spend much more money, which is why advertising is so successful.