This police bunch, it is worth noting, is the police force of the "square mile"
Indeed. This is specifically the police force of the City of London "square mile", i.e. the historic, tiny core of London, long-dominated by financial businesses, and not the police force of London as a whole.
In fact, the rest of London is served by the Metropolitan Police Service. Why would the City need its own special police force? Hmm...
which is pretty much run by private corporations, making this essentially a private police force in government-backed livery. It is not strange that it would be acting "proactive" and "innovative" and whatnot in furtherance of private corporate goals.
This article may also be of interest.