There are several credit cards that offer good cash back for gas purchases, but none of them match the power of transferable points (https://awardcracker.com/do-not-waste-your-credit-points-on-travel-portals/).
Amex Business Gold
The Amex Business Gold Card earns 4x points per dollar spent in the two top categories each month ($150,000 cap per calendar year) which includes airfare purchased directly from airlines, gas stations, restaurants (including takeout/delivery), advertising, technology purchases, and shipping (see screenshot below from my Amex statement).
Citi Premier
Citi Premier is my favorite card to use overseas since it earns 3x points per dollar spent at gas stations, hotels, restaurants, and supermarkets (see image below from my Citi statement after recent trips from Sweden, Mexico and Argentina).
Chase Freedom Flex
The Chase Freedom Flex is a no annual fee card that earns 5 points per dollar (transferable when combined with Sapphire cards) on up to $1,500 spent on a rotating set of quarterly bonus categories that can include gas purchases. I personally prefer using the other two cards mentioned above for consistent earnings without looking for quarterly announcements.
Wyndham Rewards Earner Business Card
Wyndham Rewards Earner Business Card earns an incredible 8 x points for gas purchases along with 10% award discounts and an annual bonus of 15,000 points. While these are non-transferable points, they can be used to book Vacasa vacation rentals (must call 800-441-1034 to book) for 15,000 or 30,000 points per bedroom per night. For example, spending $1625 for gas on this credit card will earn 13000 (1625×8) points that can be used to book a free Vacasa hotel night (15000 points minus 10% card holder benefit). However, finding single bedroom Vacasa properties (inclusive of all taxes/fees) in a desired location is difficult after a recent devaluation (price cap of $250/15K points to $500/30K points per night).
Conclusion
I predominantly use Citi Premier for gas due to worldwide acceptance compared to the Amex Business Gold card. I don’t think I will keep paying the annual fee for the Amex Business Gold card for the sake of earning one extra point on the gas purchases.