I was chagrined, however, when I passed by the Señor Sisig truck parked at its usual Ellis and Powell St. spot recently and noticed a sandwich board sign in its queuing area reading, in large letters, "NO CASH PAYMENTS ACCEPTED." The same signs, with nary a "Sorry" evident, were plastered on the side of the truck: The only explanation offered on the sign was that it was done to allow them to "focus more on the guest experience."
Some further elucidation was provided on SS's Instagram account, primarily related to the burden of counting cash and keeping accounts of it. They also mentioned reducing the possibility of theft, but the pedestrian activity and law enforcement presence are both so high at that location that such an occurrence seems unlikely. All reasons cited related to improving convenience for the vendor, not the customer. It goes without saying, too, that there is a cost to implementing a POS system, which gets passed on to the customers.
Señor Sisig serves an area hard by the Powell St. cable car turntable which has a significant population of street people who have to cobble together small amounts of cash to get a bite to eat, as well as many tourists who are loathe to go through the hassle of having their foreign credit cards vetted to purchase a sisig taco. For these groups, the truck's cashless system is at best an inconvenience, and at worst premeditated discrimination against cash-dependent people. In effect, it creates a two-tier caste system, the tech "haves" and the "have nots," with the latter group completely denied access to its services.
The United States long ago abandoned the Gold Standard and, as of yet, has not adopted the Silicon Standard. The Señor Sisig truck has a franchise to serve food for profit on a public street. As part of its franchise, it should be prohibited from discriminating against people who prefer to pay with coin of the realm.