> SF I think requires you to take cash as legal tender though so it's not allowed there. I don't know anything specifically about SF, but just to note that the

> SF I think requires you to take cash as legal tender though so it's not allowed there. I don't know anything specifically about SF, but just to note that the term "legal tender" specifically refers to payment for a debt. Since most retail business require payment before giving customers their goods, no debt is actually incurred. Table-service restaurants are a common exception to this, where you eat first and then pay, but counter-server restaurants often require you to pay up front when you make your order.