Jon and I were discussing the calorie-counter diets vs. low-carb diets and came to the conclusion that they had the same basic effect. He is just finishing up a low-carb diet as I start my probably-futile low calorie diet. I hope I can be as diligent as he was, except for this one McDonald's misstep.
We and Tom were at McDonald's only because it is a tradition we have, to go to McDonald's for dinner on the first day of school even though neither Jon nor Tom have been in school in quite a few years. Some traditions may be silly but die hard, especially when McDonald's fries, a guilty pleasure, are in any way involved.