SF started out with a very large Italian and Irish population, and first they get drunk, and then they start criminal syndicates. So the Bay Area has a pretty big Mafia/Cosa Nostra/Mob presence in some of the traditional areas. Waste management, vending machines, gambling, prostitution and drugs. So yeah, we got our Vinnies and Guidos and a Kevin or two you don't want to mess with either.
But what we also had, and never noticed till it was generations and generations too late, was a huge influx of Chinese persons, and they brought the Triad/Tong system with them, and that level of criminal organization makes the Italian/Irish/Jewish gang deal look like low-level amateurs.