Never assume an event will bring more clients to a city hosting it. Athletes who are mostly young and in great shape will just have sex with each other instead of hiring, while reporters and others might be too busy to hire and go out of the village to do it. Considering how expensive flights and hotels are fans may not have money to treat themselves, besides they usually travel with family or friends and not by themselves like business travelers.
Here in DC we had 20,000 librarians in town during a week for a convention, hotel prices were through the roof, one escort I know got one call.