However, I felt better on the way back (it's around a 15-minute walk each way), because right before I got to the 7-11, somebody in a car asked me for directions, and for once I was able to actually tell them. (They were looking for the airport, and I gave them a rough description about how to get back on the freeway 880 south--well, I don't know for sure that they got off of it, but it seems likely, people aren't generally in the area of my office except if they just got off it.)
But then I was almost back to the office, and another car stopped, asking for directions. The guy holds up a map, and asks "how do I get here". The here he's pointing at is SF or the Bay Bridge. I clarify to make sure that's really what he wants, point at 880 on the map and tell him he wants to go north on that, and then start giving him directions for how to get on 880 north. He says, oh that's ok, they just got off the freeway, they can find their way back to it.
So apparently, they weren't so much needing directions as being utterly clueless how to use a map. Which is rather frightening