Ask HN: Why Google does not allow "pinch to zoom" on their mobile pages?

My wife and I are frustrated that Google (Google News, their blogs, etc.) is not allowing "pinch to zoom" on their pages optimized for mobile and tablets.<p>I'm not designer nor user experience engineer, so I would like to understand why did they decided that.<p>(It is true that some other websites are doing that but they can be easily ignored: if a website does not allow "pinch to zoom" and text is too small - we can just ignore that website. But Google is hard to ignore.)