I think dedicated cheese mongers are a lot more accessible than you are envisioning based on your experience. I live in Denver, which is a large city but by no means one of the largest in the country. We have no Michelin star restaurants that I know of, we don't have a dairy industry or anything like that. We still have multiple dedicated cheese stores in the area that one can get to. It's not that niche to enjoy good cheese.
I wouldn't call it niche I just don't think "gourmet cheese store" is accessible to the average American. You can buy plenty good cheese at the supermarket.
