Yes there is. Oil is no different from any other commodity, and when something is expected to disrupt supplies, people rush to buy more of it in the near term so that they can be sure that they'll have it before it runs out. Everything I say is absolutely true. Just take a moment to study economics and you'll see that.
And as for your argument that we cannot control how much of a commodity will be available, that's also not true. OPEC is a cartel, and if it cuts production (assuming none of its members cheats), world oil prices will go up; that's a given. How much suppliers are willing to supply depends on the price; the higher the price, the more they're going to want to produce, because the more money they'll make. The lower the price, the less they're going to want to produce because they're going to want to wait for prices to go up before they produce more.
Now look you just countered you own argument...We cannot control the supply of a commodity but we can by pumping more or less oil so it is controlled, and therefore not a true commodity. We can create a artificial shortage or glut, so you actually agreed with what I said without realizing it. A commodity is a future market item, one we have no actual control over, once on the market is is no longer a commodity but a wholesale or retail item.
There is no gamble on some natural disaster killing off the crop that can never be replaced. They will always pump oil out of the ground until they run dry, by that day they will have figured some way to make enough oil from old biomass or to mine the hydrocarbons from the atmosphere of Jupiter. Until that day it will still not be a commodity as long as I can say pump me some out of the ground. By your logic Water is a commodity after all I pump it out of the ground, everyone needs it, and all rush to buy it in a disaster, so want me to open the faucet and pour you some? It's a bargain at fifty bucks a barrel!
People do not rush out to buy more if oil, we buy the final product once the refiners are though with it, N they can set up to produce more of a specific product in the cracking process within limits. As I said before we can only store so much of the stuff, so a panic buy is a very temporary thing, although my PU has a 37 gallon tank I cannot put in 40 gallons any more than you can over fill your tank and this can all be calculated by trending the market, the only limiting factor is the delivery system and the amount of refined fuel in the ground at any particular moment of time.