I guess I am playing the devil's advocate here, because I totally do not agree.
I guess this would be me, too. It seems like when I hear these type of "fair wage" arguments, the presumption is that the employers can pay more and they're just being "cheap" to put it in the most kindly terms.
My father owned a business where he *could not* pay more, or he would have been out of business. The business was so marginal that went the government slightly shifted their policy and reduce the number of clients, he went into bankruptcy. Businesses have to be profitable to sustain themselves.
Part of the high cost of living in San Francisco is actually a high minimum wage itself. If a no-education job that could be done by anyone is set at $11 when the market rate is $5, then by definition all wages will go up by the relative $6 to keep the market in balance. (Setting a minimum wage does not affect the supply/demand ratios of unskilled vs. skilled workers.) That creates inflation which increase the prices of hard goods. On the flip side, any service done by minimum wage workers will also have to cost more for the underlying business to see any profit. All of that translates to continuous cost of living spirals. (San Francisco has also instituted rent caps (the last time I checked) that discourage new landlords and building, also making the cost of living go up.)
In addition, if an employer really needs (and can sustain) two $5 per hour workers, but can only hire one at $11, they choose to never expand at all because the math isn't working. There's a strong argument that minimum wages hurt the out of work uneducated work force at the expense of those who already have a job.
Ultimately, IMO there's no such thing as a "fair wage" -- there's only the wage you can get for your services. (CEO pay is hardly "fair" relative to most workers.) Good employers are generous already as they know turn over and poor customer service is expensive. I think leaving businesses alone to set wages/benefits and dealing with social problems outside of the job realm is much more effective.