The US wants the price of gas to be higher

The US has enough reserve petroleum to lower the price to $1-2 per gallon, but chooses not to.  So many other products rely on petroleum that lowering their price would only hurt the economy, causing a surplus that would end more jobs, just like overproducing crops hurts farmers.  Also, the price of oil needs to go up a lot before oil shale becomes economically feasible. 

Estimates vary, but gas could be $6-8 per gallon before oil shale is cost effective, due to mining costs and the expensive extraction process.  Several billions of barrel of oil can be produced from natural oil shale reserves, but companies want to wait so they can mine and process this resource when it will be most beneficial to board members and shareholders, boosting stock prices to record levels.  If the US tapped into its liquid oil reserves now, prices would remain too low for too long to take advantage of oil shale in a reasonable timeframe. 

lern2 supply and demand

Farmers
Mr. FruityCollegeSocialist has an acre of shitty soil and an acre of fertile soil.
Next door Mr. LaissezFaire also has 10 acres of shitty soil and 10 acres of fertile soil.
At full utilisation they can produce 20000 potatoes for $2 each having to spend money on fertiliser for potatoes in the shitty field.
If they only use their fertile field they produce 10000 potatoes for $1 each.

Mr. FruityCollegeSocialist goes for the full utilization option.
Mr. LaissezFaire researches the market and discovers the village consumes 20000 potatoes a year but only pays $1.1 for them and chooses only to utilize the fertile field.

Come harvest Mr. FruityCollegeSocialist throws a hissy fit, screaming and crying like a total faggot claiming Mr. LaissezFaire is underproducing on purpose to increase the cost of potatoes and that this is somehow a crime, to which Mr. LaissezFaire replies in a mature manner "It is not my fault you  decided to spend more money producing potatoes than their predicted market value..".