I have limited experience with Facebook, but this sounds like a "fine print" to me. You assume that it is customer's responsibility to learn FB advertising mode

I have limited experience with Facebook, but this sounds like a "fine print" to me. You assume that it is customer's responsibility to learn FB advertising model down to smallest details and navigate carefully around technicalities in order not to drain resources to click farms. While legal, such practices are dubious. It is FB responsibility to filter out garbage and provide clean service to paying customers.