I think the reasons are that although you get a higher milage people prefer petrol because : 1. Petrol has been the mostly used fuel in passenger cars for decades. 2. The notion is only commercial vehicles use diesel 3. A new diesel car costs more than petrol counterpart. 4. A worn-out diesel is a pain to start while a worn-out petrol engine can still be started relatively easily. 5. New European petrol vehicles are very fuel efficient, taken in account the small difference in price between petrol and diesel and the rel. big gap in new diesel<>petrol car prices it can easily be counted that the difference in fuel prices will pay off after years and some people don't plan to own the car for many years. 6. There definitely is a difference in acceleration for example, even with the newest CDI engine one can feel it is more sluggish than a petrol engine. Etc etc.