In the 1970s long lines at gas stations were caused primarily by what?

Retail gas vendors, "gas stations", have to pay up front for the gas they will ultimately sell. When gas prices are volatile and fluctuate wildly, the retailers have to accept all the speculative risk when they purchase the gas. If they pay too much at a temporary peak in gas prices, and then the price goes down sharply, they are forced to compete with other retailers who purchased their supply a little later at a much lower price and can therefore sell at a lower price. This means the retailer either "waits it out" and refuses to sell gas until the price goes back up, or sells at a loss. Contrary to general understanding, retailers make very little money on gasoline, perhaps a few pennies on the gallon. The converse scenario also exists where the retailer can be in a position to make a better profit if the supply is obtained at a low point, and the prices rise rapidly.

Ultimately the consumer is affected because fewer stations have gas when retailer hold off on refueling or just don't sell gas, creating lines and the well known panic that we have seen and are seeing again in 11/2012 NY/NJ areas.

The price volatility may not be as significant a factor in 2012 NY/NJ in the overall crisis, as there other factors, like structural damage to deployment technology along the distribution chain that is preventing delivery. However, it is likely that the perception of potential volatility around the national elections has had some negative impact...