[...]what then has caused the recent rise in prices? Three related things, or so it seems: surging demand; petroleum-distribution bottlenecks, especially in the United States; and speculation aimed at pricing in the risk of some big future setback in supply. [...] But oil that is in principle available to meet this demand is being held up by blockages in domestic petroleum-distribution channels. This drives up gas prices, which in turn washes back on the underlying commodity. This should be temporary, however. Before long the blockages will clear, the gasoline market will stabilise and the underlying balance of supply and demand, consistent with a much lower price than $40 a barrel, should reassert itself in the market for crude.
То есть, если коротко, то нефть в данный момент дорога потому что ее нельзя сейчас превратить во что-нибудь полезное.