It's not actual fraud. You're not bound by the terms of service of ad providers. Your device is actually sending requests to the ads, which they are counting themselves to determine payment rates. If it's fraud to send ad impressions to sites I like without visiting them, it could be fraud to deny ad impressions to sites that I do visit (with my ad blocker on.)

If the sites set it up themselves, it's fraud. If you conspire with the sites to set it up, it's fraud and conspiracy to commit fraud. But if I'm prosecuted for the crime of not actually looking at ads I request, that's just a judge with an agenda. Whether it went one way or another at every layer of appeal would probably be a coin flip, though.