Phony job listings on legit job-hunting websites. One fraudulent group was listing fake jobs on CareerBuilder, which is an otherwise respectable site. The group was charging a big fee for a background check before consideration of any applicants. Federal, state and local authorities received more than 17,000 complaints filed by people who were ripped off by this particular group. And that’s just the number of people who found their way to complain. Who knows how many others were taken?
In the case of cost per mille/click, the publisher is not concerned about whether a visitor is a member of the audience that the advertiser tries to attract and is able to convert because at this point the publisher has already earned his commission. This leaves the greater, and, in case of cost per mille, the full risk and loss (if the visitor cannot be converted) to the advertiser.