Crunchbase isn't only startups (my employer is there, and we're not a startup) and not all startups raise money (we were once a startup, but were bootstrapped).
I would characterize the companies in Crunchbase as just tech companies.
It would be interesting to see how this fares per-city. States like Texas have much less population density and a ton of start-ups (looking at the list, Houston is very impressive).
It also helps that few people actually live in 60606 (population 1,682 in the 2000 census). If Mayor Daley wanted 60606 to move up on this list, I guess he could do it with some strategic zoning changes.
I would characterize the companies in Crunchbase as just tech companies.