Getting Gas for the Northbound Trip to Austin

Since I've been waking up early to run or ride 5-6 times per week, I've become habitually accustomed to getting an early start to the day.  Monday morning, I woke up at 5:15a, and was on the road to Austin by 5:45a.  I stopped at the first gas station I saw, and in the morning darkness I filled up the truck.  As I mentioned last week, I was amazed by the price:

That's right -- $1.79 per gallon.  I remember when I was in high school around 1987, and gas was $0.99 per gallon.  Some 20 years later, the price hasn't even doubled.  I bought a pair of Levi 501 jeans on Sunday, and I'm pretty sure they've more than doubled in price since 1987.  And since cotton, dye, and human labor are not scarce resources or technologically difficult to procure and manage, I'm guessing it's purely inflationary growth in price.  Oil, on the other hand, is getting harder to find and get out of the ground, even though our technology for doing so has improved, thus possibly suppressing prices TO SOME EXTENT.

How can gas be so cheap?  How can it fluctuate so drastically over just a few months?  Have our driving habits and vehicle choices already changed so much that demand has decreased, thus driving down prices?  Or is it black helicopters?  The Trilateral Commission?  The Rockefellers, the Rothschilds, and the Kennedys?  I can't figure it out.