For starters quotas are illegal. Now he may have said that because he felt you deserved a ticket but wanted to make it seem like it wasn't his decision. Some guys do this because they dont want to get yelled at. Me personally if you earned a ticket (and people really earn them through their attitudes sometimes) then I want you to know I had a choice and you earned what you got. Im guessing you probably did not have a poor attitude because youre a porsche owner and porsche owners dont have poor attitudes
Now certain things aggravate the situation. Perhaps the chief has been getting complaints about speeders through your neighborhood and sticks this guy there to quell the fire. He stops a guy in a Porsche and lo and behold its your neighborhood. If I stop a guy cruising in a nice car with little regard for the speed limit (read:flying and driving like a jag) Im probably not going to give him a warning because a warning may not prevent the behavior next time. Radar detectors also mean automatic tickets.
That said I cant tell you for sure why you got a ticket because I wasn't there and im not that cop. Porsche owners get a little sympathy from me because I have one, but I've also never stopped one because one never presented that opportunity. I can tell you that 20 over on the interstate will get you a ticket. 20 over in a residential area and you probably bought and paid for it. Do the deferral program and avoid the points hit and try to slow down next time.