I was a developer on a big data smart cities project in wellington a few years ago. I don't see how it benefits the people because it is mainly about monitoring and data gathering. People, vehicles, crime, electric vehicles, parking, roads.
For instance highly accurate people counting cameras enclose a space so real time crowd monitoring is possible.
Add mach address monitoring and to that you can monitor people moving from space to space.
Then add economic models ( for events ) which many western cities seem to have. Then city income , from say an event, can be estimated in real time.