"A party does not have a right to rely on a representation if she is aware the representation is false, not enforceable, or not made to her."
It's clearly arguable that the ad network knows that a browser is able to click on an ad in an automated fashion. Thus, they do not have a right to rely on that representation, as it is not enforceable.
[0] - http://www.mitchell-attorneys.com/legal-articles/common-law-...