When I am on the road at lunch time and haven't thought to pack a lunch (Duh!) I don't look for golden arches, but a grocery store. Many groceries have a salad bar where I can make a spinach salad with tuna or grilled chicken. Fruit makes a great dessert. I am not tempted by soda or fries, and get several servings of fruits and veggies in my noon time meal, often for less money than a fast food meal.
If they don't have a salad bar there are many pre-packaged salads, and a deli to add some chicken breast or tuna from packages instead of cans.