perhaps there's an internet exchange in one of the Graceville's, and it accounts for traffic from nearby cities too? I noticed that San Jose makes the list, as

perhaps there's an internet exchange in one of the Graceville's, and it accounts for traffic from nearby cities too? I noticed that San Jose makes the list, as does LA and Seattle right now, but no San Francisco. I suspect that SF traffic goes through San Jose and thus most of the bay area appears as San Jose in their numbers. Not a big leap to imagine this happens in other places too.