The size of the hamburgers shown on tv is so different from what you get when you go buy one.
Can they be sued? Sure. Will a complaint like this go very far? No.
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My colleague is correct. Suit is possible, but major franchisors have massive teams of in-house and outside counsel who protect their client's vigorously. In addition, there is the issue of damages. Unless it is a class action (which is very, very complex) the amount of your damages probably don't exceed $5.
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