Fasting is one way, yes.
My favourite diner meal is steak and eggs with bacon and sausage, hold the toast, hold the potatoes. I find that most diners are perfectly willing to serve meals without bread or potatoes, and many will offer extra vegetables to make up for the missing potato.
A lot of convenience stores these days also sell pre-cooked bacon and hard-boiled eggs. One thing I regret about living in the boondocks is the serious shortage of Korean delis around here. When I was working in New York, the Korean delis always had a table of prepared dishes and salad fixings so you could mix and match to suit.
You can also pack a cooler bag with your own pre-cooked bacon wrapped around some cream cheese, a hunk of hard cheese (I like buttered cheese, myself), some pepperoni, or some leftover meat. Stick in a bag of pork rinds, and you’re good to go. If you rummage around the forums, especially in the Newbies section and the Food section, you’ll find plenty of other tips.