You may notice that in Europe, Asia, the demographics of restaurants are noticeably different from the US. There are far more hole-in-the-wall mom-and-pop restaurants in those places compared to the US, running a small and seemingly profit-thin but subsistence restaurant for the neighborhood. Think of a suburban neighborhood in Madrid or Rome, where a small restaurant is just as common as a tabacchi / corner convenience store.
I believe (have not seen a careful study yet) that the rent-seeking / zoning policies of our cities in the US increase greatly the cost of running restaurants. And incentivize / prohibit anything but large commercial / chain places from surviving as a rule. It makes it very hard for small experiments or small-time mom-and-pop shops to survive and stay in a community for decades at the low profits those places are willing to accept. There may also be something about the small square footage of typical shops in such cities being unfavorable towards chain restaurants which seem to require a certain size (like hotel properties).
The landscape of our policies for cities, neighborhoods, plus the way they interact with our corporations, directly translates into the kinds of restaurants that we get as a result.