Columbus, Ohio, with a population of over 700,000, is the fifteenth largest city in the US.

I didn't know how big Columbus was! I still don't think the parents came off that badly - merely stolid and old-fashioned in a way that's as much a generational thing as anything else - but I suppose by making them from the Midwest the story does pander to the idea that the area is behind the cultural curve. I wouldn't say it's a major issue but it's the same attitude that US television often takes when portraying the UK, ironically.