Are gas stations tricking us ?
I think what you may have done inadvertently is filled up with the wrong gas. I have seen some stations who color code their gas grades with certain colors and then other gas stations will use that color for regular unleaded, for example, on their premium unleaded gas pump options, thereby tricking the user into thinking that color represents regular unldeaded. Just my theory on what coulda happened. Those pumps are highly regulated by the weights and measures deptartment cause gas pump fixing used to be a big thing back in the day, so doubt they did a switcheroo on you.
