The causation more likely goes the other way: When an area gets the reputation of being higher crime (because of reality or because of bias from more police saturation), that area becomes cheaper to live in, and poorer people can then afford to live there.
I don't think it's more police presence that causes banks to install the armor. More likely it's the lack of police presence that results in armored banks.
Definitely my Bank of America branch in Ballard doesn’t have bullet proof glass.
Isn’t that called de-gentrification, or maybe ghetto-ization? However, I think it’s the opposite with property crime (richer neighborhoods attract property crime because their is lots of property to steal).