As I read this a while back ( I think a week ago) My first thought was that the expense of security guards are a repetitive cost as compared to a one time for the security glass.
Security cameras are there for the cops to see the affects AFTER the crime, NOT TO PREVENT IT.
Not if you know Philly politics. I live fifteen miles southwest of Philly and follow its news. In my experience of the last twenty years living here, the Philadelphia city council gets its members from the Darwin Award winners.