Lawsuit.........

I don't know about the lawsuit part for sure, but I would say that any store selling food products shouldn't be selling potentially risky food, whether it's outdated or not. When we go to a grocery (or store) to buy food, it's generally accepted that the foods on it's shelf are within the expiration date listed on it, and if not, they are discarded. What I would do is talk to your local Health Department and make it known to them so that they can check that store out and do an inspection. Once you have done that, and reported that you became sick from that food purchased there, then you very well might have grounds, and proof, of misconduct, or mishandling of food products. Hopefully you saved the box, or whatever, the food came in. It would probably be hard to prove that you bought it there, but if you made your concerns known to your local Health Department, then they are forced to check out the issue. If you became sick from it, also let them know that. Arm yourself with the facts: the date you purchased it, what the food was, and if/when you got sick, and etc. Keep these facts written down for yourself in case a suit DOES come out of it. Once the Health Dept is aware, it would be much easier to prove because it would be documented that you came to them to complain about it.