It was a sales gimmick adopted years ago when a penny mattered.
This. I remember my Dad driving past a station that had gas for .60. He knew the next station had gas for .59. Today, the difference between $4.39 and $4.40 isn't worth the extra drive.
At todays prices it isn't worth going past a station with gas 10 cents higher.
I always did get a kick out of the people who wouldn't go to a gas station for a penny or 5 difference. In the typical 20 gallon tank, 5 cents is only a dollar difference. Even at 10 cents, its only 2 dollars difference.. With the prices now, 20 gallons at 10 cents difference is only a 2% difference or less (much less in CA, NY). Much bigger deal when gas is sub a dollar, but at 4+ dollar gas, 10 cents is silly to worry about.
I know, every dollar counts.