Trust me. A LOT of pros eat regular American foods regularly. I know a couple pros pretty well that are local here. When in prep it's a different story though they still will cheat once a week or at least every 10 days or so and have burgers pizza whatever. Not everybody does but many do. When you are at a certain level you know your body and you know what you can and cant do. No matter what level you are at, nobody needs to live their life trapped as a zealot. Never let your lifestyle get in the way of life.