Twice a year when it is time for the seasonal formulation changes, the refiners all act like it is some big surprise. "Oh noes! A seasonal formulation change? We had no idea THAT was going to happen! And just when we shut half our capacity down for maintenance at one plant and set another one on fire! Oh well, guess we just have to jack up the prices. Drat!
Like clockwork, they use the formulation change regulation to manipulate the market, spike the prices and line their pockets. It is profiteering at its worst.
ETA: Very similar to how the power company always seems caught off-guard by people needing more electricity when the thermometer heads for triple digits.