In my country sometimes, very rarely, a cop in uniform will stop you in the street and ask for your ID. It will happen only in suspicious environments like bus stops of railway stations, usually in the middle of the night. I think this is not that usual in USA so the people that visited me were sometimes surprised about this because allegedly it is not common in USA.
Similarly, sometimes when I read posts about US (traffic?) cops on forums, I wonder if your traffic cops are idiots or what. In my country no cop would question the displacement of my vehicle. Vehicles have yearly inspection, 50 cc vehicle has a small license plate and that's it. If you have some mods that are not legal and certified (for example, exhaust), you could be removed from the traffic and sent to extraordinary technical inspection. Cops do not tow the vehicle, you have to do it and you are not allowed to operate it until this is cleared. However, you really have to make some crazy mods to be treated that way.
Here cops also like to ask if there is a warrant against you, or if you were ever convicted for something. I think you have a difference between misdemeanor and felony, and they are asking about felony... they should not ask such questions because if they want, they can check that over radio link. Also, even if you were convicted for something and you paid your dues, you are a "free" citizen and cannot be judged because of that offense. However, they still ask that question and I usually respond to get rid of them, even though I work for judiciary branch of government and know my rights better than most. The problem is that any time crossing borders or getting pulled over for me is full-blown "investigation" because my head is shaved and I usually hover around 240 lbs so I am the usual suspect...
Another thing is that they like to ask you to show them your car gear, like accident reflective triangle, tow rope, spare set of bulbs etc. They ask you that not to check the gear because it is checked by the inspector during annual inspection, but to see what is in your trunk.
I realize that in USA cops usually have a lot of time, or they are bored because during stops cops here check a) validity of your driver's license b) validity of your yearly technical inspection (vehicle papers - if they are valid, this automatically means the car is insured). Maybe, just maybe, they will check if everything is OK with lights of the car. 30 minutes seems excessive and I certainly hope "your" cop felt stupid for harassing you. Another option is to check you for DUI using "breathalizer" or test you for drugs.
What would happen if you had plenty of time and told him "please, tow it away, no problem with me". The guy is an idiot.
I already told you that in most of the Europe, fluo lights similar to ones you have are a reason to be forbidden to join traffic. In my country you could get a nice fine and be sent to technical inspection and I agree with that. There is no place for additional lights other than "white" lite in front and red in the back of the vehicle, and yellow for blinkers (red in USA) and white reverse light.
Police statistics for my country can be found on
http://www.mup.hr/UserDocsImages/statistika/2010/statistika_engleski_2009.pdf , page 23. refers to traffic safety.
