Sorry still to go on about the incident that TDM and other describe. But, even if the Approach Radar is only contracted to provide a service to IFR flights, surely the co-ordination procedures between ADC/APP require radar to be advised of outbound (or any known) VFR traffic that is headinfg toward the FAT so that radar can provide appropriate traffic information.
And back to the ATSIN, I agree that telling a pilot what service he is receiving will not prevent an incident/AIRPROX from occurring. But we have to work with what we are given and I would prefer to have to tell the pilot what he's getting (although getting the readback is too challenging sometimes) than have to try and explain why I ignored the rules to a judge!