You've been lucky, or simply just didn't have the cars for long enough to see the fuel pump go out but this kind of treatment will definitely put significant wear on it. In the same way that a sample of 1 is unrepresentative of many other avenues in life, it doesn't prove anything. There are always people who smoked two packs of cigarettes a day and lived to 90, but extrapolate the trend out over 100,000 people and see what you find 🙂