I spend all day driving for my job. Most of my eating is done in the car. I keep a small cooler in the front floorboard with bottled water, peeled boiled eggs, Luna bars, apples, bananas and sometimes raw carrots, celery, broccoli, cauliflower and peppers.
If I find myself without enough food packed for the day or if I'm bored with what I have I stop at a convenience store for low sodium beef jerky (not all that healthy but 3oz is 150 cal and really fills you up). The bigger stores, like Pilot, Loves, etc (the big truck stops) often have Lara bars, Cliff bars and some fresh fruit at the counter.
If I want something hot, Taco Bell is my go to - one fresco chicken soft taco is 150 cal and always satisfies my need for warm, real food.