With Vancouver I was fortunate that the coastal city had a wealth of sushi options. Sushi rolls were an almost perfect combination of carbohydrates (from the rice) and protein (from the fish, seaweed and soy sauce). Sure, they also had markets with lots of produce, which also helped.
But produce is easy to get in most locales. Rich healthy whole food carb and protein sources… not as much.
Running the Chicago Marathon in October makes this easy since it’s only a few miles down the street. I can cook and eat as typically desired right up to and after the race. To a lesser but still reasonable extent, the nearby Fox Valley Marathon and Milwaukee Lakefront Marathon are close enough that if I ran either of them I could eat normally up to race day.
So, what if I ran a marathon in a more remote locale, where there’s not a lot of stores and restaurants? Or even if it was a major market, what if pretty much every restaurant available served processed and otherwise unhealthy food that wasn’t going to help me stay ready to run?