That sounds horrible. You're already not sleeping much, cramped in a car for hour after hour.. why would you do this to yourself?
Similar to this rule is don't eat bad food and don't gorge yourself on food that you do eat. A cheeseburger and some fries from McDonald's won't hurt you, but going to White Castle and eating a 10 sack of sliders does not make for a good chase. Eating several five-layer burritos from Taco Bell and thinking of washing it down with a liter of apple juice? You might want to think again. Thankfully, I haven't had to learn either rule the hard way.