If you east of Los Angeles to Pomona or Ontario it's about a dollar a gallon less. Or at least it was 9/16/23 when I was there last. I have no doubt that Los Angeles is that expensive because I saw gas stations out where I was that expensive as well.
Years ago (more like decades ago now) when I lived there, Arco was where you went to get the lowest price for gas. I was shocked to see Arco wasn't much different than 76, Chevron, Shell, etc. You have to go to the brands no one ever heard of before (and didn't exist when I lived there) to get the lowest price.