Those higher power cars run higher octane to prevent detonation, not because their car can't run without it. They run it simply because they need it to get the power they want, some even have to run race fuel to achieve this.
Now, take our motor/car. The motor was designed from the get-go to run regular unleaded gasoline. Sure, you can put 93 in it but it will really be a waste of time unless you have the MP3 ECU because our motors aren't high compression and thus you might think you're seeing an improvement but really most people are just trying to justify their extra dollars spent on a tank of gas.
