Update: The promotion start dates differ depending on which area you are in. Make sure to check your local circular for the promotional details in your area.
From June 5 through June 11, 2015 Giant and Stop & Shop will be offering 3X Fuel Points for the purchase of Visa gift cards. While Visa gift cards do not normally earn fuel points, during this promotion, each dollar spent will earn 3 fuel points.
For example, purchasing a $500 Visa gift card will earn you 1,500 fuel points. Those points are worth $1.50 off per gallon of gas up to 35 gallons. That represents a potential value of $52.50 from the purchase of just one Visa gift card.
For more information about the deal, how to use the fuel points and a photo of the ad, see this Doctor of Credit post.