No premium involved. I have multiple friends who know something about gasoline prices and have seen wholesale price schedules and non blended fuel costs less.
One of my friends family owns a bunch of large Cstores. They were one of the last of the bigger operators around here to convert to blended ethanol fuels. One of the reasons it happened so quickly was the "walmart syndrome". People were shopping only on price not value and a gas station operator could buy blended fuel for $0.09~0.11 less/gallon. So if you owned a station everyone just knew you were ripping them off by selling them non-blended for more money. Eventually all had to convert.
It would actually go up.
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