Consumer preference and demographics are the driving forces.

Fast casual meals are often coming in at the same price point and generally of better quality. Most dinners aren't interested in sitting down for an hour + meal that is generally not on par with the fast casual alternatives.

Inside the city, there is a whole host of options to complete with ENP, specialty brunch spots weren't a thing 20yrs ago. ENP realized fast casual/changing consumer preference and targeted these crowds by way of SixPenn(RIP), The Porch, Hello Bistro.

Denny's, ENP, King's, Bob Evans are all dinosaurs that aren't bringing in business when there is an abundance of competition. Years ago, their competition was probably dinners, but most dinners have closed up in favor of these newer age alternatives. If you look around the city, there just aren't many sit down restaurant chains.

So, outside the city, life moves a bit slower, considerably less competition from the brunch & mimosa, more families on family budgets, etc.