The wast majority of websites with ads get paid per clicked ad or per sold unit/registration. They don't get paid a single dime for visitors that do not click on the ads (see https://en.wikipedia.org/wiki/Compensation_methods). The big exception is video and video sites where commercials has a different purpose and economic model (branding mostly).
That means, if one never click on ads on a website, it's equivalent to running ad-block on your browser. There is no moral superior choice by allowing ads to run on the screen. When we do, we are just fooling ourself into believing we are "contributing". At worst, we get a worse impression of the website and thus won't encourage others users who would click on the ad to visits the website.
However, I doubt this has anything to do with economics and all to do with the ap-market and it's image. Google want to encourage new developers to code for the Google Play market place, and thus anything that might scare away developers is a threat.