I'm all for this, but just to give you an example:

I know someone who read a web forum. People wanted an ad free paid version for years, so he eventually added it at a cost of $15 per year. Most users balked at the price. 'Why did you add this if it was so expensive'?

Well it turns out he actually earned more revenue from advertising to frequent users. He was actually losing money on each person who paid, and it was still too expensive!

My point being: I think we might underestimate how much our attention is worth. Most people are not willing to pay as much to avoid an ad as an advertise would pay for you to view it.