For instance I worked for a B2B startup that had joined an accelerator near Union Square in NYC and it was a great situation. For one thing NYC is the best place to be for B2B sales into a wide range of industries, but the connections that the investors and other participants in the accelerator bring really help.
Once you have a sales playbook that works, VC money is really like rocket fuel for hiring more salespeople and speeding up your process. You might think that spending money on TV, print or web ads would also benefit, and I'm sure it does, but it's a very different thing to be talking to consumers over that kind of 1-way channel as opposed to a "high touch" sales process where sometimes getting the customer to talk is the best technique you've got.