I just took a 3 day trip and finding a decent restaurant that wasn't overcrowded/too expensive was impossible, so the only food out we had was McDick's.  I gorged a bit trying out local snacks too.  Gained a grand total of 4oz.  Fats can't go anywhere without gaining 5-10lbs.  I've eaten McDonald's cheeseburgers on 1200cal diets, it's a perfect little cheat when you want some crap.