I think it's a better deal to simply eat at cheaper restaurants! There are oodles of ways to save money on eating out, but a very limited number of ways to get miles for something you do anyway, even if you go somewhere else and pay a bit more to do it, it's still way less expensive than buying miles.

So that's why I personally don't see the value of the cashback program, though if it's free now I guess it can't hurt if you don't want any of the airline/hotel programs.

Because they give me miles I can't easily get elsewhere, I go out of my way to mostly eat at participating restaurants. But if I didn't earn miles, I'd simply eat at cheaper restaurants. Why worry about saving 15% at restaurants that are 20% more expensive, when you can just eat anywhere the prices look good and you're actually more likely to save more money that way?

(Now, if one or two of the restaurants that you'd eat at anyway, even if they're not in the program, are in the program, well, then, that's the one case where I guess I'd see how it's worth it, if you have no interest in points/miles.)

But if you have no interest in points/miles, may I ask why you're on a forum called FlyerTalk?