There are seasonal formulations. There are formulations demanded by regional and state agencies. There are formulations to address differences in altitude and climate. There are formulations that address brand-related 'advantages' and performance differentiation.
I believe there is sufficient 'national interest' to justify intervention by the federal government with policies that would simplify and standardize the regulations that lead to this proliferation of formulations.
- Reduce the number of octane levels to two (though a mid-grade might be offered as the pump-produced mix of low and high octane formulations).
- Require that automotive diesel be available at all retail dispensers (utilizing the now available third storage tank).
- Reduce the regional variations to those that minimize consumption, e.g., those that address climate and altitude requirements.
I believe that states would acquiesce to these federal standards as they become convinced that there is a comprehensive federal energy policy.