Reducing waste is like performance optimization - you should only do it once your code is correct. The original poster just paid $1000 for a meal probably consisting of fish that was pulled from the ocean on the other side of the planet 12 hours ago. The resource cost of acquiring this food, preparing it, and operating the restaurant will dwarf the cost of a nice receipt. If you prefer, they could hand write it on nice post consumer recycled stationary to save some "trees".