Most of our refined fuels come from BP Whiting which on Lake Michigan near Chicago.
Being near an oil shipping port is good. However state gas taxes play a role. June 2019 AARP Bulletin had a Check to Tax map on page 40. States over 40c tax are CA 54.4, PA 58.7, NY 44.1, FL 42.0, IL 42.9, WA 49.4, NJ 41.4. States between 21c and 17c tax are AZ, NM, TX, LA, MS, OK, MO, SC, VA. All the rest lie between 21 and 40 cents per gallon. When I used to drive to Florida to see my son, I would fill up in Virginia, and when I arrived and left South Carolina.