Remember that (assuming this is real), that money isn't really coming from Google. Google actually makes money from AdSense. So this should really be called Google AdSense Advertisers Will Eat Google.
GAAWEG: Kinda a long name, but I would still prefer GAAWEG with a reasonable background to GWEI with this blinding background.
Basically that Google is aware they are using robots in conjunction with AdSense and despite the fact that Google understands this is an art project, Google has to defend its AdSense program as well as its advertisers from harm. Based on the material on the web site itself, Google believes the GWEI people give the impression that their project is violating the AdSense TOS. Google will unequivocally defend its rights and this generally includes shutting down the AdSense accounts of violators. Google also reserves the right to take additional action.
I.e. not quite a takedown letter. More like "we're watching carefully".
"By establishing this autocannibalistic model we deconstruct the new global advertisment mechanisms by rendering them into a surreal click-based economic model."
I'm pretty sure it would be trivial to write a program that automatically generates modern "art" exhibit descriptions like this one.