I agree, they probably are be safer, but they are harder to contol at higher speeds. A stock car is more than 2 times as heavy as an open wheel car and the tire is less then twice as narrow. The handling is totally different. Open wheel cars like IRL, F1, and CART, can adjust the handling on their cars with buttons on the steering wheel. So as the car uses fuel, it gets lighter and the handling changes or if the track gets warmer or colder due to weather conditions the handling changes. Stock cars can't do this, they need to come into the pits to make adjustments.
