When you buy a photography magazine, it might have 20% of the pages covered by advertising. I'd say most people buying the magazine find them useful. Maybe only 1% convert to a sale, but I'd say the majority of people find the adverts useful.
Also, it's not a black and white thing between "content" and "advertising". For example, quite often adverts in digital camera magazines are handy for me because they show me new products or lenses I didn't know about - Those adverts are 'content'.
I'm not going to convince anyone who hates advertising to open their mind a little though, so I'll retire happily to my ad-supported magazines, and ad-supported websites.
People also come across thousands of ads that they ignore every day in billboards, shopping windows etc. That's not a legitimate reason to rule out advertising as a revenue option. (On the other hand, claiming that the majority of people find them useful is a bit of a stretch)
Not 0.05% that's insanely low.
Mind you, a lot of those sites (the high end, anyway) are optimized strongly for clicks. The ads show up in the middle of content (as an "interlude") or prominently above the fold.