It's not that different. There are 43 police forces in the country, with different specialities, and the City of London force leads (not very well) on financial crime. Businesses do have a vote in local elections, but that was standard across the UK until the Representation of the People Act 1969. The Corporation of London is basically just a local council like any other, albeit with a load of money and a load of meaningless ceremonies (both for historical reasons).