Safety is one of industry's major standards today, and some auto makes like Volvo take it very seriously, almost as the central pillar of the design of a new car. It would be nice to have some kind of institution inside the game which do crash tests in your cars. Good results coming from a well planned structural resistance would boost the car sales, meanwhile poor results would provoke a deep fall in the sales.
But if a car is too cheap, even a poor result would not affect the sales. Look at some of Brazilian and Chinese cars, which show almost none structural/torsional resistance. They sell a lot, because they're cheap (quite cheap here, but Brazil is another world...) and who buys one of those do not have much concerns about safety.