Stainless steel. Because the common understanding of stainless is not what the stainless in stainless steel means.
Organic foods. Obviously this varies by location, but there are no universally standardized and enforced definitions of what it means to be organic that it comes close to being meaningless. You'd be surprised at what "organic" growers can get away with.
Genuine leather. It's so misleading it's pretty easy to argue that it's essentially a lie.
20% off. When it's the same cost as it was last month, you just upped the price, then put it on sale, so that in the end it evens out.
Genuine leather is leather in the same way that an egg taped to a box of Betty Crocker cake mix doused in a cup of oil is a cake.