The reality is that few people will do this as long as it's optional. The masses are short-sighted. For anything like this to work, a publisher needs to block the display of their content if ad-blocking is in place. They could bring up something that says "you have one of two choices: go to <Google contributor-like network> and pay, or disable your adblocker". If people run into this enough, they'll do one or the other.