If I - and everyone else - could quickly identify which bank/gas station was acting in my interest without colluding, I would immediately switch.
The fact that prices are quick to rise but slow to fall is dependent on consumer apathy and monopolistic behaviour/collusion.
It might be typical market behaviour, but it's not the perfect market that economists commonly base their models on.
I doubt this would be the case for most people for a couple of reasons.
First, gas stations are pretty transactional businesses that don’t rely on recurring customer relationships to stay afloat, it’s really all about the location. When was the last time you researched all the gas stations in your area and looked for the one that you felt served your interests above all the others? Nobody shops for gas this way.
Second, when gas stations maintain prices as their upstream costs come down to pad their margins, they’re doing so in cents per gallon, not dollars. A customer may save a dollar or two depending on the size of their tank, which isn’t enough of an incentive to stick it to the greedy gas station because you gotta be sure that the next gas station you’re headed to isn’t doing the same thing or costs even more. The gas station, OTOH, probably sees hundreds if not thousands of dollars in extra revenue per day depending on their volume for doing this.
I do. I own a classic(ish) car that both requires high octane gas and no ethanol. There's one gas station chain around that can be relied on to have it (in addition to every other fuel option imaginable). But I'm a relatively price-insensitive customer; I'd probably still buy from them at $5/gallon when others are at $2.50. Part of that is because of being happy with the chain, and part of it is anger at other chains for dropping non-ethanol options.
Your claim is that the gas station has a monopoly over its location and is therefore able to engage in monopolistic behaviour and depend on consumer apathy - this does not really negate my point.
It works best in industries with no real competition because of the high barrier of entry, and with a common interest between the players to keep the practice going, even when there's no explicit collusion or cartel forming.
You own a gas station and you want to fill up your tanks so you call the distributor and pay $1 / gallon. You then sell that for $1.10 / gallon making a 10% profit.
Now prices of crude doubles and you have 1000 gallons left to sell. It’s going to cost you $2 / gal to refill so you immediately raise your price to prevent a loss and cover the next fill.
I don’t know how accurate that is to the real situation gas stations face but I’d never thought of it in terms of selling higher to afford the next bulk delivery.
But your competitor will lower their prices when they get a refill, so you may end up having to lower your prices before you get your own refill.
The big oil company uses futures and options to manage risk.
All aspects of that industry have slowly reconsolidated, so the market forces that push prices down are generally weak.
There are exceptions (e.g. near airport rental car returns, or in places where drivers aren't paying for their own gas — there used to be a Shell near San Mateo City Hall that always got on the front page of newspapers)
The situation with the banks is slightly different.
The odds that the product, money, will cost more for them in the future does not line up with the recent history of bailouts, regulation changes, etc.
During Katrina, for example, it was a safe bet for the gas station owners that the next batch of gasoline could cost significantly more. A reasonable assumption due to the multiple wars in the middle east combined with a bad hurricane season shutting down gulf coast refineries.
In other words, the Federal Reserve did not run a discount window to provide cheap oil to gas stations. Even the strategic petroleum reserve, if tapped, would only benefit the refineries.
At any rate, one could argue that in both situations the entities involved made the safest and most profitable decision available to them.
The same exact thing happens with gas stations. The price of gas never falls quite as fast or far for the consumer as it does for the retailer, but gas stations will instantly respond to price increases. I’m sure there are dozens of other examples of this.