If anything, this change at American Express makes its cards less attractive with cardholders. If you can easily get juicy cashback up to 6% at Citi's Driver's Edge (pfblog review) with no annual fee, why should you pay to join Amex's mediocre reward program?

As part of a sweeping overhaul of its cardholder rewards programs, American Express Co. will no longer give its customers double rewards points when they use plastic for "everyday spending" at supermarkets, drug stores and gas stations.

The move is one of a number of changes being announced today to American Express's Membership Rewards program, one of the card industry's most successful plans aimed at building customer loyalty. Other changes include a new double-points program to encourage online shopping at certain retailers, the elimination of a free rewards program on some of its cards and a new insurance plan that will reimburse certain cardholders who miss concerts, plays or sporting events if they purchased their tickets with an American Express card.

Consumers are likely to feel the changes starting as soon as next month. Some cardholders may see their annual card fees rise as much as $35 to a new level of $125; others may see their fees decline based on the type of card that they carry. American Express says it will start notifying cardholders about the changes in their August bills.

The overhaul comes as American Express and other card issuers are scrambling to grab a larger share of consumer wallets. At the same time, they are also grappling with the high costs associated with rapidly-expanding and creative rewards programs that now let consumers redeem their points for such varied purposes as plane tickets, massages or a pet's next trip to the vet.