LIke the cost of attending a university, the costs of living in major cities such as New York, Washington DC, San Francisco, LA, and so forth have exceeded the rate of inflation for a long period of time. There has to be a price correction sooner or later.
The interesting thing is that this calculation works if you have one or two clients there. But as the number of clients grows, there has to be a break-even point. Also note that they're billing the travel hours of the attorney.
Still, this is a warning shot across the bow for the state of California and the city of San Francisco that their economy won't support continued growth if they keep doing what they're doing.