Many states etc do not enforce the door sticker numbers either. Here in Wa state, ALL trucks pay tonnage fees. Pay per 2000 lbs, and are legal to the paid for 2000 lbs increment from 4000 on up. Min you pay is 1.5 times the tare, base wt of a truck. If it weights 7000 lbs empty, 1.5 is 10500, you pay to the next higher ton, or 12K lbs. Does not matter that the door sticker says say 9900 lbs, you are legal to 12K gvw mind you. This transfers state to state from what I under stand too.
Of course, if you do as I have done with my C2500, bought an 8K sticker, I am legal to 8000 lbs, NOT the 8600 lb door sticker!
Reality is, in my mind not less, our gvw from the manufacture, should be the sum of the axel ratings, NOT a lowered warranty number! My 02 only of course, we know how far that 02 goes these days.....
Marty