> In the US, roughly 5% of households earn more than $200k. In a town of 70k, you’d expect there to be roughly 27k households and therefore 1300 households earning more than $200k.
This assumes uniform distribution of household incomes across cities of different sizes, which I suspect is a shaky assumption. More likely, the high earning households are concentrated in a short list of major population centers.
Not as much as you think. I couldn't quickly find the dataset where I looked at this before, but https://statisticalatlas.com/United-States/Household-Income has percentages of population earning more than $200k by state and MSA. The Birmingham Alabama metro area has 4.03% of its households earning more than $200k, and Alabama a whole has 2.92% of household earning more than $200k (the 5th lowest in the Union, btw). That means Alabama outside its biggest, richest city is still 2.5% over $200k. Sure, those are also probably concentrated in the other 2nd cities in the state like Montgomery and Tuscaloosa, but you are getting really far down the list of US Metro areas by population when you get to Tuscaloosa Alabama.
There are well off people throughout the United State, not only in the top 20 metros.
This assumes uniform distribution of household incomes across cities of different sizes, which I suspect is a shaky assumption. More likely, the high earning households are concentrated in a short list of major population centers.