By far the biggest danger for children wandering around (in rural area, suburb, or city) is big cars moving quickly. But none of the suburbanites worried about cities seem to mind that there are SUVs whizzing around their residential neighborhoods at 40+ miles per hour. (Or more realistically, plenty do worry, and keep the kids indoors or drive them everywhere instead of letting them wander around independently.)

> Statistically speaking the schools in the city are going to score lower

This has more to do with the more diverse mix of children in the class than it does to do with school or teacher quality per se.

But I'm happy to grant you that some upper middle class parents are also inordinately worried that their children might spend too much time near poorer children who get worse test scores because their families have fewer resources and they were not as academically prepared.