You don’t have to use a model which allows this. Pay-per-placement, for example. You pay a fixed amount to put your ad in a specific article (or on the entire site or in whatever rotation people like) and then there’s no way to rip off advertisers with click farms.

You still need to measure your audience to get advertisers to pay the price, but this is decoupled from the individual ad buys so it can be done differently.