It's hard to make a case like this, because Google returns different results to different people. If I type "buy ping pong balls" into Google, the results I get will be quite different from the results someone else gets.
The difference depends on (a) where you are (which country), (b) whether you're logged in to any Google service, and (c) whether there are Google cookies on your machine (and let's face it, unless you've taken extraordinary measures to prevent it, there are). Google's rankings are kept opaque - purposely, because that's the only way it can work, but as always with secrecy, it makes abuse incredibly hard to investigate.
Biting the hand that feeds IT
