I don't know man, gas prices have been consistently pretty high for the last couple of years, meanwhile almost every small car has been discontinued- VW Beetle and Golf, Fiat 500, Honda Fit, Ford Fiesta and Focus, etc... this class of cars basically just doesn't exist anymore.
I think everyone drives less in California than in Florida. (Google says ~14,500 miles annually per licensed driver in Florida, versus ~12,500 miles in California.) Gas prices are a factor in this.
California law requires a special blend of gasoline, which is a lower volume market, which increases the cost. The remainder of the cost difference is transportation costs or taxes.