Once approved under AdSense program, this assures that your website meets the stringent condition set including Google Publisher Policies. Once a visitor visits your website and sees AdSense ads, he or she can be convinced that they are not into a site with dangerous or derogatory content, content with animal cruelty, unreliable and harmful claims, malicious or unwanted software.
Even when monetized by affiliate marketing, an AdSense approved website means a visitor assured not into a pure or ‘thin’ affiliate website since the website passes webmaster guidelines by Google AdSense on affiliate programs.
Not surprising, AdSense approved websites are scarce than other genres. When put for sale on Flippa, here are the screenshots that gives a sense: Only 413 AdSense websites listed in an instance against 2441 in WordPress, 6209 online businesses, 706 Amazon FBA stores & Amazon affiliate sites.