I think you've fallen into the old trap of mixing up terminology - there's no such thing as 'VFR conditions' and you presumably mean VMC.
Actually no I am not, I understand perfectly the terminology. Us Instructors get to learn all about it you know.
If one is operating under VFR then one has to be operating in VMC. The fact that others are flying under VFR and asking for a FIS would indicate that the conditions are VMC as well. Unless of course our intrepid hero is accusing others of illegal flight?
So as I said, claiming to be IFR in VMC in order to get a better service is in my humble opinion reprehensible. While the controller is busy giving our friend a full radar service, the service to others asking for a FIS and a zone crossing is reduced needlessly.
Sometimes people sit and complain how they don't get zone crossings due to controller workload........