If grocery stores, which operate on about a 6% margin can have them, It seems to me that for a minimal cost most restaurant chains would do well to incorporate a swipe card of some type to reward frequent users.

Starbucks comes to mind, as they seem to be everywhere now. There are huge amounts of people that go to them everyday at home and look for them when they travel. They could have special "express" lines for elites,etc.

I think that restaurants as diverse as McDonalds and Ruth's Chris could benefit from a FF-like program.

Many restaurants have them, but don't advertise them.

Best example: The Palm (steakhouses) They have the 837 Club.

In Bangkok, I've noticed that many local and international chains, as well as a number of one-off's, have discount cards and/or frequent diner programs. A few which come to mind are: MK, Black Canyon, Sizzler, Fuji, Daidomon, See Fa, S&P, and dozens more that I could list if I pull out my cards. As a matter of fact, it almost seems like sport in BKK to see who has the thickest wallet full of dining cards.