Wow, look at all the responses and downvotes. More privileged assholes with money to burn feel it's fine to spend $10 on a meal and just throw it away. Just because there is so must waste doesn't mean that you have to behave like you don't know the value of money.
What things do you feel it's acceptable to throw away without being a privileged asshole? Is there a way you made this decision that can be generalized beyond Big Macs?