TSBOregon has the 44th highest gas price in the country right now, and Colorado sell 85 octane because of the altitude. That aside both states are great having lived in both of them. The pumping gas thing is great but I'd rather save $5 every time I fill up.
That is not actually true if you compare 87 octane instead of comparing regular gas. Here in Salem a gallon of 87 Octane is $2.26 right now. Where my in-laws live in Boulder the cheapest 87 octane is $2.40.
There is a station owned by Kroger here is Salem (Fred Meyer) and their current price is $2.33 per gallon, the Kroger owned station in Boulder (King Soopers) is currently $2.43 per gallon.
I have always found the best prices on gas here in Oregon.
Modern fuel injected cars actually run best on the fuel they were designed to run on no matter what the altitude. No cars sold in America are designed to run on 85 octane. The fuel lobby has more influence in some states so they use that influence to sell inferior gas and pocket more cash.