You generally can't shot them right off the bat, but in most places you can use non-deadly force to defend property, and if the thief responds by threatening you with death or great bodily harm, you can then use deadly force.
In some states, if you reasonably fear that using non-deadly force to stop someone from committing arson, burglary, robbery, or felonious property destruction would put you in danger of serious bodily harm, you can skip straight to deadly force.
That's good! Deadly force should only be used to prevent serious physical harm. It should be pretty easy to trace those people and put them in jail. But I'm sure the SF police didn't even bother.
Does SF prosecute petty theft? In Seattle we mostly don't, and haven't for years. As a result, there's usually not much point for police to put petty thieves in jail.
I'm not even sure they investigate/prosecute class C felony theft here much anymore. Above $5,000 stolen (class B felony theft), and then maybe there's a case.