Blizzard deals with most game exploits the easy way: account ban or suspension, depending on severity and how quick they hotfixed it. To my knowledge, Blizz has only gone legal against players for modifying the game client's code and hosting private World of Warcraft servers (the latter for attracting unsubscribed players, IIRC).
What part of "an algorithm's result depends on users' input (that's plural in cases of multiple sources, FYI)" did you not learn in high school? Google can't control what other users type into the search field.
In the words of a brilliant scholar: "Shit goes in, shit comes out; the math gives no shits."