Further trivia: this scene was shot Candid Camera style, with Koenig and Nichols accosting real tourists. The cop is part of the film unit, but the woman in the scene who says she thinks its in Alameda isn't exactly an actress.

According to the woman's entry at a Star Trek database:

"After her car was towed from the filming location on Grant Avenue in 1986, [Layla] Sarakalo decided to stay on the location and earn her money that day as a background performer. She was a member of the group of extras who were instructed to interact with the two actors, but she ignored the instructions given to them that they should not speak while on camera. She said, "Oh, I don't know if I know the answer to that. I think it's across the bay. In Alameda!" The crew decided that her exchange with the actors fit the scene, and kept it in the film. Sarakalo did not realize until the film was released that her scene had not landed on the cutting room floor."

http://memory-alpha.org/wiki/Layla_Sarakalo