While I wouldn't deny that there's a lot of bloat in the SF city government, I think it's important to take into account that SF is both a city and a county (a "consolidated city-county".) Hence, the SF budget has to make room for the functions would usually be left to the county, e.g., sheriff+jails, public works, parks, assessor, coroner, etc., and probably a whole bunch of other stuff I'm missing. That could explain some of the apparent budget inflation w/r/t Chicago.