The price of gasoline and diesel fuel amaze me, regardless of when prices are high or low. I often harass my friend who is the general manager at a major gas station about his prices, and he often jokingly responds that his bonus is based upon how high he can keep his gas prices for specific periods of time. Needless to say, that upsets me even more and I usually trade a few insults with him about his business methodology. My friend's business tends to be the price leader in town, signalling the price of gasoline and diesel simply by the price he displays on his billboard. Other gas stations in town follow his price increase or decrease within a few hours, except for those who claim to have specialty gasolines with proprietary additives.
Outside of two major national gas stations, all of the gasoline in town and most of southern Utah comes from the same pipeline about 10 miles west of Cedar City. This brings up another interesting point in that prices for gasoline at the same gas stations (example: Maverick) are about $0.25 higher in Cedar City over that of St. George, yet all of the gasoline comes from that same pipeline west of Cedar City! When I ask those gas stations in Cedar City why they are about $0.25 higher than St. George, they claim extra "transportation" charges (but as mentioned, all of the gasoline comes from west of Cedar City), so I feel like I'm getting ripped off....and I hate getting ripped off by a bunch of profiteering clowns.
So what causes price changes in gasoline and other petroleum products? The Economist does a pretty good high-level review: http://www.economist.com/blogs/economist-explains/2014/12/economist-explains-4.
My reasons for caring about gasoline and diesel prices are very legitimate. I work in the transportation industry, where my yearly local and regional diesel fuel consumption exceeds 4.5 million gallons a year, so every penny counts. The Economist web link above, summarized, proposes that supply and demand are not the only determinants of price. Weather and geographic location also play an important role. Some topics worth reading comments on: 1.) Does everyone feel gasoline price differences between cities in Southern Utah are reasonable or unfair? 2.) Does product differentiation (bulk gasoline vs. name brand gasoline) warrant local price differences? 3.) Why the sudden rapid gasoline price drop? Is there a hidden agenda?