Okay, Perhaps $13.00 was a slight embellishment..
I figure the cost of a big mac alone would be in the 7 dollar range in San Francisco...at present with taxes it is probably $5.09 including taxes
If I owned a McDonald's and the starting wage was $15.00. I'd probably go fully automated, lay-off 50% of the employees and cut the hours of the rest to absolute minimum..
A big mac, alone (not the meal) is $3.99 + tax. It comes out to around $4.30.
Since you don't own a McDonald's, you have no reference as to what the profit margins are, and what changes these wages would require. Talking about "going fully automated" (which would involve millions of dollars in initial investment) and firing half of your workers is meaningless because you don't actually know what you're talking about.