Food service on commercial flights became the norm after 1936, when United Airlines installed the first onboard kitchen. Typically reheated on board, in-flight meals are often the butt of jokes due to their reputedly poor taste—though the food may not be to blame, as some studies suggest that high altitude and cabin pressure interfere with taste buds. In recent years, many airlines have cut back on meal service in order to cut costs. How much did one airline save by eliminating free pretzels? Discuss