PLAN AHEAD! That's my biggest suggestion, pack a breakfast, lunch and snacks every day, so you have no reason to go to those horrible places to eat when you're on the road. You have to make the time for this, I do a lot of cooking on Sunday and then just throw it in containers and its ready to go all week. I have cauliflower pizza, you can eat that cold, I have cauliflower sausage bake, you can eat that cold, tuna salad, chicken salad, cold chicken. etc... you can do this.. but plan ahead.
Well, I certainly can't speak for everybody but I had no stomach for fast food. (get the pun?). Really, I just didn't WANT that unhealthy stuff!
Can you travel with a little cooler of your own food? Yogurt, protein drink, those small 4 oz Breakstone cottage cheese, turkey and cheese wrap?
I was going to say the same thing..invest in a cooler (there are more expensive ones that you can plug into one of those doohickies on your console..lol..forgot what they're called)..pack all the things you need for your day..it'll probably be more effective if you make a weekly menu, so that each morning all you have to do is look at what you need for the day and put it in your cooler and you can be out the door real quick. If you have it on hand, then you shouldn't need to go through a drive thru or walk into any kind of restaurant except to use the rest room :)