Shell focuses on delivering high quality fuel for performance and expensive cars. It is endorsed by Ferrari and targets an upper-class audience. Its fuel costs more but provides better performance. For expensive cars that can utilize premium fuel, the value outweighs cheaper options.
Tesco focuses on affordable fuel prices over quality. It targets a wide range of customers, including existing supermarket shoppers. While some argue better-branded fuel is needed for performance cars, Tesco fuel provides good value for most vehicles. Tesco competes with other supermarkets for overall customers and fuel sales.