Well, driving with a suspended regestration is of all things irresponsible. Insurance companies see this information as it is provided to them from the department of motor vehicles. This tells the insurance company that you cannot maintain regestraion which translates to you not being able to maintain constant insurance for your motor vehicle.
Basically the laws in some states says that in order to regester a vehicle you have to provide valid up to date automotive insurance, or insurance consistant with the vehicle or device being used. But once a default on regestration occurs, the insurance company reserves the right to terminate insurance. This makes the driver all the more likely to suffer a worse penalty if they are pulled over for a traffic infraction. For one, no insurance or regestration is a severe violation in some states. These situations if ignored, can also lead to the loss of all driving privlages. Once your driver's licence is lost, then being pulled over can result in a charge of aggrivated unlicensed opperation of a motor vehicle, which is a felony charge in the state of New York.
To add to this mess of consequences, the department of motor vehicles can enforce their own brand of justice. For every day that either insurance or regestraion has lapsed, a fee may be imposed. They could range to 8 dollars a day all the way to a flat fine of over 500 dollars just to be able to take the test to begin to get your licence back. There is alot of paper work and time involved with getting things strait and right after letting your insurance or regestration lapse on you.
Something else to think about is the fact that if your vehicle is not regestered, you cannot have license plates or have your vehicle inspected for safety. Without license plates, your vehicle is deemed illegal by the local authorities and you would be commiting a crime by driving it on public roads. Not having a required motor vehicle safety inspection can affect more than just yourself. Without a proper inspection the vehicle cannot be completely checked for safety defects that may put the lives or safety of others at risk, all the while making the opperator of the vehicle fully liable and responsible for all damages and criminal charges resulting from the lack of regestration, insurance, and a safety and emmisions inspection.