Isaiah, serious question-do you do your own groceries and do you cook/prepare your own meals at home? As others have said, this will give you an idea of what you eat/spend now, but really the issue here is that a lot of people who don't cook or buy prepared meals are going to spend a lot more per day than someone who has experience preparing meals that use less expensive ingrediants but still are healthy, filling foods that give good energy over a longer period (as opposed to lets say, eating cookies and chocolate bars--the far end of the spectrum but perhaps you know what I mean)

eating a meal at a restaurant sometimes will also be a money factor. There may be times you arrive somewhere and there are no grocery stores around, only a mom and pop restaurant, you are pooped, hungry, so eating at the restaurant is handy for getting a meal in and getting to bed faster.