Do you have that backwards? Did you mean they only accept cash in L.A.? Or that they don't accept cash?
In San Francisco, some stores on downtown Market Street tried to institute a non-cash policy, refusing to allow cash transactions. City Hall came down hard on them to reverse the policy, saying it discriminates against poor people who don't have credit cards or debit cards. Which is okay with me, as I try to pay cash for most purchases (I don't like having my spending habits tracked).
SNAP cards which were supposed to
eliminate the stigma of being on the dole
apparently didn’t count