Why is it still the same price difference in grades of gas?

Question

back when regular was, say, $0.99, midgrade was about $1.09. that's about a 10% increase in price.. now that regular is about $3.99, midgrade is not $4.09, a 2.5% increase.. gas companies seem to stick with the $0.10 increase per grade.. seems that if regular went to $50.00, midgrade would be $50.10. im not complainig, it just seems like there is something shady going on. the're telling me that no matter how much oil costs, it only costs $0.10/gallon to raise the grade? again, this seems SHADY, gas companies are getting over on us.. could somebody somewhat explain the prices?

Answer 1

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Answer 2

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