That's what I'm saying, the ad exchanges say they know how to detect the cheats, but they don't actually do a good job of it. And it's not really in their interest to do so. They get paid equally for ad-fraud as they do for legitimate impressions. The person actually advertise the product or service gets shafted. But as long as there is a long tail of people like me when I first got started who don't understand the issue of ad fraud (and the complicit people who sing the praises of advertising to boost the idea that it's a good path), the ad exchange will keep raking in money, just like the people committing the fraud.

It's easy to look at this as "Farmers vs. Google AdWords" or whatever other ad exchange we might consider. But Google is just a middle-man. And as long as the system works for some definition of "works", they can capitalize on asymmetric information about the ad industry to bleed money out of small actors.

With online advertising, it's exceptionally easy to end up in a situation where everyone gets paid except you.