5th, and actual most common reason.
They don't know any better.
I'm dead serious. This came up at the last state gathering of concealed weapons instructors and the state Bureau of Criminal Identification (which takes care of permits in Utah).
Most of the problem cops are relatively new. When informed about the gun, they don't know what to do, so they disarm the CCW holder. Usually out of ignorance about officer safety.
This problem has been getting steadily better in recent years as permit holders become more and more common. We pushed for a unit to be inserted into the police academy curriculum about it, but nothing resulted, mostly from lack of time.
That said, there still is that small percentage that are just doofuses that fit into your reason 1-4. PvtPyle got pulled over the other day by one who was a complete jerk. They are out there.
And in defense of the original poster, I've been pulled over seven or eight times in the six years that I've carried a gun here. Never for excessive speeding, but usually because the speed limit is about ten miles an hour less than it should be.
I've only gotten one ticket in my life and that was in California. (there is no way that a highway across the middle of the fricking desert should be 55 mph). Everytime I've been pulled over in Utah, I've been armed, usually much better than the officer, and I've only gotten warnings.
I was pulled over once in the middle of nowhere. 75 in a 65. (didn't even realize it was a 65). I had 2 guns on my person. Body armor on the seat next to me. A Wasatch plate carrier full of loaded magazines. And six rifles and shotguns in the back seat, all of them ARs, AKs, or Saigas.
Got a warning to slow it down.
I love Utah.