It doesn't, really. It's just that these companies tend to draw more modest valuations, generating a more subdued kind of excitement. Forbes just wrote about how VCs should invest more in B2C startups [1]. A different piece from CB Insights last year [2] argues the same point. There are some VCs who specialize in B2C stuff, Maveron [3] being notable on the West Coast. Mostly, though, this capital does not concentrate in a small area like SV.

[1] http://www.forbes.com/sites/chrismyers/2017/01/09/why-entrep... [2] https://www.cbinsights.com/blog/vc-investing-in-consumer-goo... [3] https://en.wikipedia.org/wiki/Maveron