*shrugs* I dunno, I figure there's a good reason for most of the questions they're asking me (so far they've all been related to the stop in some way) and I have no problem answering reasonable questions.
When I first visited Arizona, I had some plastic license plate cover over my rear license plate to keep rain, mud, etc. off. Evidently this violated some sort of law in Arizona, and I was pulled over by a highway patrol officer. I had crossed the state line about 25 miles before, and was exercising my right to open carry.
After stopping, I turned off the car, rolled down the passenger window, and had my hands on the wheel.
The conversation went something like this:
Me: Good afternoon, officer.
Officer: Good afternoon. Do you know why I stopped you?
M: No.
O: You have a plastic cover on your rear license plate. That is not allowed here in Arizona.
M: My apologies, officer. I was unaware of that law. I would be happy to remove the cover now, if you wish.
O: That won't be necessary. Where are you heading today?
M: Scottsdale, sir. I'm visiting a friend for a week.
O: I see. May I have your license, registration, and proof of insurance?
M: Of course. Before I retrieve them, I would like to inform you that I am legally carrying a pistol on my left hip.
O: What type of pistol?
M: A Glock 19, sir.
O: How do you like it?
M: [briefly puzzled] Quite well. It's fun, inexpensive to shoot, and is quite accurate at the range. It fits me quite well.
O: Excellent, the department issues us Sigs, and I own two Sigs of my own but I've been looking at getting a Glock for a while now. As long as your pistol stays in its holster, there won't be a problem.
M: Not a problem officer. [retrieve license, registration, insurance, hand them to the officer]
[officer returns to his cruiser, does Cop Stuff(tm) for 5 minutes or so, and returns with a warning]
O: I'm going to give you a fix-it ticket for your license plate cover. In the event that you get pulled over by someone else between here and Scottsdale, just show them this and they'll let you proceed. Just be sure to remove it once you get to Scottsdale. Once you do so, you can mail in the form saying you took care of it. Sign here, please.
M: [signs] Thank you officer, have a good day.
O: You too. [returns to cruiser and departs while I start my car and carry on my trip]
I figure a lot of the questions the police ask during a stop are to "size up" the person being stopped, and get a better feel if they're a "good guy" or "bad guy". I strive to be a law-abiding person (I certainly didn't intend to violate the law against the license plate cover), and try to present myself that way to the police officer. If I were confrontational or failed to answer reasonable questions, I suspect things might have turned out for the worse.
That said, I would not consent to a search of my vehicle (nothing to hide, but I value my privacy) or reveal any information which I felt the officer had no business knowing and had no legal authority to require.
Hell, even when I was driving a hatchback in California and had a gun in the car (a cased, unloaded Kel-Tec SU-16B), I had to stop at a DUI checkpoint one night along with all the other cars on this particular road. The officer asked how my friend and I were doing, and if we'd be drinking. We hadn't, and responded accordingly. He asked what was in the rifle case in the back (he could see through the rear window). I responded "a rifle, sir". He asked what kind and if I liked it. I responded that it was a Kel-Tec SU-16B, and I liked it quite a bit, though the handguards did get warm when one was doing drills at the range. He nodded and waved us through after suggesting that we remove the rifle from the car when not in transit between home and the range (I had just gotten out of the range a few hours ago, and hadn't had time to stop off at home yet). No big deal.
Ok, this post is quite a bit longer than I had expected, but I think it gets the point across, even if I do ramble a bit.