Years ago, I tore up my Texaco card and started using my Amex Starwoods card for all gas purchases. Why pay an extra bill and why give up the bonus?
A few months ago, I noticed the local Citgo consistently had the best gas prices in my area. While filling the tank, I notice an offer for a Citgo card with a 4% cash back on gas purchases. Over the course of a year, I expect to save approximately $100.
For people with large families full of drivers, this strategy could really pay off.