Sending automated clicks to ads arguably meets all the elements of common-law fraud:
(1) A false representation of fact (that the user clicked on the ad);
(2) Knowledge of the falsity (by the user installing and using the extension);
(3) Intent to deceive the party by making the false representation (that is the extension's stated purpose!);
(4) Reasonable reliance by the innocent party (by believing the "click" was real and intended);
(5) Actual loss suffered (by paying the owner/operator of the page containing the ad)
In my view, therefore, "fraud" is an applicable term.
(Not saying that I do that, of course. Entirely hypothetical.)
"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-...
This would be like if you are a dairy farmer and you notice people who buy cookies usually buy milk, so to make things simple you make an agreement to pay a store 25 cents for every cookie they sell (because you want to incentivize them to sell more cookies and therefore more milk). You couldn't then accuse a customer of fraud when they buy cookies but not milk. They never agreed to always buy milk when they buy cookies, that was just an assumption you made.
I think you are deceiving everyone that you are indeed an attorney.
Whatever the merits of that argument might be in the general case, using an extension which expressly advertises its function to include falsifying clicks to mislead ad networks makes it hard to make the argument in that context.