Just, anecdotally, I knew a startup in northwest Arkansas (the walmart region) that won seed funding of about $100,000. They squandered the money relatively quickly, and immediately decided the only way to salvage their business was to head to SF. It only took a few months after renting a house to keep everyone in, and they managed to secure another ≈$1.3M. To this day they swear up and down, the only way to turn a business idea into reality is to live in SF/the valley. Seems to be a very common concept, regardless of the realities.