Race cars are using motors with extremely high compressions. More compression means more power (Simple definition, applicable in this explanation). Those drag cars run so much compression that the motor is only good for a couple runs. Unless you modified the engine, you only need to run the minimum octane. Those octane boosters are good for people who have turbo engines that have modified their turbo computer making even more boost thus more compression. The biggest lie is that it makes all cars go faster. Only a handful of cars benefit from octane booster.
Fuel system cleaner is a little controversial but I don't use it in any of my new model cars, MB is adamant about no fuel cleaners. I only put a bottle in my 300E lately because I will replace my O2 sensor soon and fuel filter and I have new fuel pumps. If you are going to use cleaners just techron or valvoline synpower..nothing else. Also a common fallacy is that you add the cleaner after an oil change. You want to add it a tank before the oil change so that you can drain all the crap that comes out. By adding cleaners, you are putting a number of components at risk. Everything in the fuel system, and sensitive O2 sensors + cats are put at risk. My recomendation, go get your car serviced than wasting money on these snake oils.