Dado, people travel through all of those states daily and do not get killed. As for the NW, hasn't Seattle already met its all time highest yearly murder rate and the year is only half over? Nothing against Seattle, it's a great town but every where can be dangerous. Hell, I am sure there are places in the Netherlands you do not go at certain times. It is certainly true for large cities in other parts of Europe.
One road side eatery in that part of the US (and pretty much on Interstates everywhere) is Cracker Barrel. It is your general heart attack on a plate, southern cooking. That said they do have low carb options if you swing that way. I bring them up not because the food is great but because they are everywhere. You should be able to get some decent BBQ in Tennessee and seafood along the coast of Mississippi and FL.
Carls Jr as someone else mentioned has burgers wrapped in lettuce which work and most places will do their best to meet your requests (as long as they are not too outlandish). I've had luck just trying local places along the way. The best BBQ I have ever had was in Louisiana at some random interstate exit. The building looked like a shack that was ready to fall down but I would slap my mother to eat those ribs again. (Then I would run because she would slap me back )
If you want heavy cream at Starbucks you can order a latte 'breve' Usually they have half-and-half out to put into regular coffee. That said, I wouldn't worry about the lingo too much. Just tell them what you want. "Yeah, a coffee with some heavy cream in it" or whatever. That said, many places in the US are waking up to quality coffee so again you may want to try local places if you find them.
somehow I manage to leave my intelligence and decorum at the door wherever I go. I doubt your journal will be an exception to that - not on the rug
What the F&#* is a decorum? - Mr. Anthony