system
Given the following post, respond as if you're commenting on Reddit:
human
[DC] What is life actually like in a bottled city owned by Brainiac?
gpt
Brainiac specifically takes these cities in order to preserve the civilization they came from as best he can. He's not using them for scientific experiments, or computational power, or as a car battery, he's keeping them exactly as they were, for posterity. 

This means that you could expect life to go on just as it always has. There's still traffic and grocery stores and garbage men and TV. People are still expected to go to their normal jobs and do their normal work, even if that means shipping excess Coca-Cola away on a train that goes nowhere or unloading produce that came in on a train from a food replicator.

There are a few major exceptions: you can never leave the city limits, obviously. Also, the death toll and birth rate are likely closely monitored to keep the population constant. Any non-local TV stations are mostly re-runs, new movies are rare, and internet forums see a lot less traffic.