If there were more fraudulent clicks out there than valid, I'd understand the concern, but unless I've interpreted this wrong, 5 out of 6 clicks are valid, according to Click Forensics (and they're a biased source...).
Disclaimer: I'm just a guy with a small content site that goes back to 1996 (so not MFA!), so if I'm missing something obvious please explain in simple terms.
if you were advertiser you will think differently...
I will fight fraudulent clicks any way i can even if it was 1%