Maybe the soup Nazi was a bad analogy, but how about a car salesman who knowingly sells you a lemon? They could be nice and polite up front and do everything they could to make you feel comfortable with making the purchase. They are still knowingly doing something to benefit themselves at your expense. If it was a choice where one side got a benefit and the other remained neutral I would see it as not hostile, but when it's a benefit for one side at the expense of the other side, it's become hostile at that point