When I created a spending tracker a few years ago, I broke down grocery receipts into a few different categories, one being junk food. It has really helped with the budget and the calories.
I did the same for my category for the grandkids. We are always taking them places so find that we grab a bite out instead of eating at home. So I track restaurant food and junk food for them as well. We seldom eat out, and I learned most of the time when we did, it was with the grands.
I agree that cutting out unnecessary food and eating out saves calories and money!