This is part of the reason the Google Safe Browsing project was created. At the time there were a lot of malicious sites either trying to get high SEO or paying

This is part of the reason the Google Safe Browsing project was created. At the time there were a lot of malicious sites either trying to get high SEO or paying for ads. The goal was to make it safe(r) to go to google and search (and click!) on things. For a project that didn't directly make money (there are some 'cloud' offerings now), Safe Browsing probably was a very high return on investment.