I fear you may be unaware of how petroleum is extruded and processed. Before crude oil is even useable for highly valuable fuel it must be discovered and removed. This dynamic and lengthy process shows that oil is relatively rare and relatively – to most other things in general – hard to remove and contain. Water is otherwise. It falls from the sky via a highly regular and sustainable cycle as it’s fueled by the abundant and constant energy of a star and the abundant and constant existence of shit-tons-of-water at surface level on our planet. Even when drilling a well for water the burden is not the same as for crude oil drilling; the rock and pressures required are in favor for water wells due to pressure of flow requirements and the rock itself.
Petroleum is clearly different in it’s cycle, as it must first be an ancient forest or something of similar biological density and then be covered and then covered again by heavy dirt and rock until squeezed by very extreme pressures until it is degraded into crude oil. It must also exist in a place reachable by humans and not dissipated through stone like shale or sandstone to the point its hidden in the rock and too hard to process (let alone if a magma chamber rose into it). Most notorious, this petroleum genesis process takes 10–100 million years depending on geological conditions and thus has no sustainability on human generational terms.
Needless-to-say-but-saying-it-anyway-because-I-have-a-fetish-for-hyphens, you should now see the difference between the water and petrol cycles and how their pricing per volume is so disproportionate.
As for storage and perishability, crude oil is pretty dense (high mass per volume) and so can be hard to manipulate outside of liquid-flow systems. It’s annoying to find a place to store it safely and surely as well. Plus, after the crude is up and out of it’s home it will contain gases that are ready to fly out of the larger mass, you have to deal with this in both extraction, storage, and refining. Still, the fact is true that crude oil should be non-perishable. Logically, it’s been in the ground under high heat and pressure for millions of years and so is pretty stable. However, that is under an anaerobic environment, meaning that it’s not exposed to a lot of oxygen. Holding it in a steel barrel could mean, over decades, oxygen could leak in and degrade some of the hydrocarbons that are useful for fuel. This would be a meager amount of oxidation and may not destroy the potential for fuel refining but it’s worth noting. Overall, the barrel of crude oil should be of energetic use (processed or otherwise) for a very long time but not indefinitely as water would. The small molecule H2O is highly stable and hard to decay over any amount of time.
Before we go and drive our car to buy some water due to the pretrol-water discussion that just makes you thirsty to drink and drive, let’s put volume in mind. There are nearly 2 billion barrels (84 billion gallons) of crude oil in reserve around the globe according to BP’s analysis. Likewise, there are 326 million trillion gallons of water on/in the Earth according to the earth science guys. That’s a 163 billion factor of all-fresh-water over crude-oil-reserves.
All-in-all (hyphens-baby!): Both give life in their own special way and each has its own rarity and supply cycle. Why price them the same?