I just talked to a restaurant owner who recently signed up with idine. Here is what I was told:

idine gives the restaurant a check for $10,000 and receives $20,000 in food revenue back. The total ticket less tip and taxes goes to idine until the debt is repaid.

This particular owner had no idea that miles can be awarded in lieu of the 20% discount.

Once the credit is repaid, the restaurant has the choice of another credit or dropping out of the program. This explains why so many drop in and out so quickly.

The $10,000/$20,000 deal is the lowest a place can sign up for.