That's why I live where I live. When I travel for work, it's the company truck where I don't pay for the fuel. I fill the tank on my LSC maybe once every 3 weeks, so it definitely wouldn't be worth a new vehicle for me anytime soon!
However, in 1995, I used to drive about 200 miles a DAY for my work, so I bought a new Mazda Protege that got 40-42 mpg. I put over 300,000 miles on that car in less than 6 years before I got rid of it. So if you figure I saved over 7000 gallons of fuel (comparing 20 mpg to 41 mpg) in the time I owned that car, that's way more than the $14,000 I spent on the car.
And for what it's worth, the insurance on that new car was WAY cheap - much cheaper than I pay now!