Why not offer two Googles, one for people who don't mind sifting through three pages of SEO results when they search for actual information, and another subscription that cuts out ads for those willing to shell the cash?
For example. If you’re looking to refinance a home loan; you’re easily worth $100-$300 of revenue to Google; with a decent number of searches and clicks (eg “refinance”, “mortgage interest calculators”, etc)