Well how does one put this delicately. Tell them to kiss your ass.
Leads and not qualified ones. You'll get low ball tire kickers and pay through the nose for them.
Use the money you would spend with them, on your own program and you'll do better at promoting your service, not theirs.
Google any service and they pop-up running ads for the same service. They then sell them back to you and any other sucker they can con.
At least your ads will be for your company, not in their rotation of distribution.