There are two big factors driving it: (1) Branding-- many companies actually maintain a faux office in the Bay Area because having a Palo Alto or Menlo Park ad

There are two big factors driving it: (1) Branding-- many companies actually maintain a faux office in the Bay Area because having a Palo Alto or Menlo Park address makes you look smarter or more legit. (2) Investors-- talent and opportunity is everywhere, but smart tech investors are super-concentrated in the Bay Area. The further you get from it the less knowledgeable and more conservative the investment climate becomes. In the long term I think (1) will fade and (2) will get disrupted by crowd funding.