Who has Google sued? Have they sued Apple for the blatant shade swipe-down feature in iOS?
Just a few years ago, in 2006 when IE no longer was the dominant browser, Google sued Microsoft over MSN being the default search engine in IE, instead of just competing:
http://blog.samat.org/2006/05/04/google-sues-microsoft-over-default-search-engine-in-internet-explorer-7
In 2010, instead of competing, Google sued the US government for preferring Microsoft:
http://articles.marketwatch.com/2010-11-01/industries/30785419_1_email-contract-google-and-microsoft-google-apps
In 2005, instead of competing, Google sued to shut down Froogles, despite them having used the name Froogle years before Google applied for the name:
http://news.cnet.com/Google-sues-Froogles.com/2100-1030_3-5676955.html
In 2004, instead of competing with a site that was launched before Google was even founded, they again sued to shut down a competitor in a market they were moving into:
http://news.cnet.com/In-name-dispute%2C-its-Googles-vs.-Google/2100-1038_3-5259688.html
Again, this is business as usual, you just never heard about it, because it was never very profitable to write about until now (with the rise of link-bait and tech blogs).