Because getting it right costs money, and lets be honest here, car modelers are cheap. Would you be willing to spend $50 on an accurate kit?? Hell, I spend $50-$70 on my tanks, $100-$150 on my planes. Why you ask?? Because those kit makers actually took the time to do the research and cut the tooling to be accurate. Are they 100% accurate, no, but pretty darn close (in the 90%-95% range) and whats not right, I correct, since I am after all a model builder and not just a kit assembler.