LOL, that is called revenue generation and it also includes income taxes, the only city where anyone actually pays income tax. Do you also think the ports and other transport hubs just work by themselves? Karachi is not your khaet where money can only be generated by selling gundum. LOL, next thing you'll tell me is that no urban city generates revenue and there is no such thing as a service industry. Singapore is in fact bankrupt too, right?
Most of the tax is colected at port, which Altaf Bhai did nto bring from Lakhnaoo, it is poperty of Pakistan not of piglet Altaf and his children.