After thinking about this some more, 2 points came to me.....
1. Suppose I'm at an Eric Clapton concert. Do I get to go backstage and see Eric? probably not, because I'm just Andy Anderson. BUT........if my name is Mick Jagger and I'm a member of the Rolling Stones, I probably get ASKED if I want to go backstage. Just about any scenario you can come up with will probably be the same. It happens EVERYWHERE to one degree or another, even with the LEO's.
2. You have NO idea what the LEO just came from! Maybe he just left the scene where a speeder hit a minivan killing or severely injuring one or more small children, or from the funeral of a co-worker. They might have just come from a situation where they got shot at. I've been shot at with the intent to kill, and I can tell you that it isn't any fun....PERIOD! YOU might just be the beneficiary of something like that and don't even have a clue what's pissing him/her off, and they DAMN SURE ain't gonna share that info with you! That's why I always try to be polite and pleasant with the LEO. Hell, if you were pulled over it was probably because you were "noticed" and deserved to be pulled over anyway.
There are probably a million more points, but these 2 just jumped out at me.,
Andy