Most premium gas is different than regular only because it has a higher octane rating. The only drivers who should bother with "premium" gas are those with higher compression or otherwise higher performance engines where the manufacturers has recommend using premium fuel. Likewise, for the rest of their vehicles/engines, manufacturers recommend regular (87 octane).
Interestingly, the gas companies used to run ads trying to convince drivers that if they wanted to "pamper" their vehicle or wanted to "clean" their fuel injectors, they should buy premium gas. This is simply misleading. Regular unleaded contains detergents just like premium and most engines are actually designed to run on 87 octane so putting premium gas in them is not just a bad idea but a waste of money.