There is no excuse for asking for a RIS/RAS in when flying VFR as you are just stretching a controller and most likely denying others a service as you become a priority.
Bollox.
(1) Why on earth is a RIS superflous when flying VFR? Yes, see and avoid is the primary means of collision avoidance, but why not make use of all available help?
(2) Inconsistent. If you believe that VFR pilots do not need a RIS, who exactly is denied service if he files IFR to get one????
RAS, on the other hand (which you will only get when IFR) is a bit of a pain in some areas for both the controller and you (how on earth will he/she achieve 5NM vertical / 3000ft vertical from unknown traffic at Ockham? Do you really want to be vectored all over the place?) so RIS should normally do the trick.
Small anecdote from my CPL training: On my first sortie with the instructor I asked habitually for a RIS. The instructor told me I should only get an FIS, and used the SOP argument when I stated I considered not using an available RIS in busy airspace somewhat lacking in airmanship. Three weeks later we had a near collision (30 ft, same level) in gin-clear VMC. Over the beer we had that evening he quietly said "I see your point now".