In the early decades of 20th century America, bars would offer a free lunch to all their customers. Of course, the lunch wasn't really free because you had to buy beer in order to get the free meal. And often the quality of the food left something to be desired. Before long most people learned that there really is no such thing as a free lunch, there is always a catch. This led American philospher, Robert Heinlein, to his famous saying, TANSTAAFL