<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Knowing how many meals to provide would be easy since the cheapest fares would need to be booked far in advance, and the higher fares would include meal service.</font>
Some airlines offer a bistro service, where you select the food you want just prior to boarding. This eliminates a lot of waste and also the extra weight of food that won't be used. I think this is something US carriers should at least consider.