I think we'd need to do some real analytics on this to see if this is true. But if it is true: people hawk their stuff or promote their company on HN all the t

I think we'd need to do some real analytics on this to see if this is true. But if it is true: people hawk their stuff or promote their company on HN all the time, including on negative articles about competitors. I have no idea why you think only Google does this, because I've seen it from startups and big tech giants alike. Google is a huge employer and Googlers could easily be one of the most overrepresented demographics on HN. In that light, it'd be pretty expected.