It’s really simple. The stores pay Ebates to send them customers. You’re kind of hacking the system a little.
I’ll give you an example: You need to buy Christmas gifts, and you know that Ebates will give you 8% of your purchase back at Amazon, so you go to Ebates first, then enter Amazon.com through them.
You spend $100 buying Christmas gifts for everyone. Amazon pays Ebates $10 for sending you to them, Ebates pays you $8 for going through them (and making them $2). Amazon is happy because they get more customers, Ebates is happy because they make money, you’re happy because you get money back…It’s a win/win/win. This method is unusual in a sense that everyone is winning.