Things tourists like to do, but that locals are pretty meh about

Alcatraz – you know, it’s an empty jail.  But it’s a nice boat ride and pretty view back to the city, so that’s nice.  If you want to go, buy tickets ASAP.  Bring a jacket, hat, scarf and mittens - even in summer.

Pier 39 – we avoid this tourist trap (in fact, I avoid from Pier 39 to Ghiradelli Square) like the plague except to bring visitors to see sea lions and ride the cable cars.  If you're taking kids, my advice is to focus on the sea lions and carousel, and set a time-limit and budget.  If you want to sit and eat by the Bay, the locals go to:

• On the pier, the only place I'd bother eating is Boudin's because it's cheap and basic. 
• Greens over at Marina Green for great vegetarian food that even meat-eaters like
• Pier 23 to sit outside and eat burgers and drink bloody mary's or whatever
• The Ferry Building - grazing the farmer's market on a Saturday is awesome.
• Red's Java House or the High Dive (conveniently across the street from Ben's new office) on the piers just south of the Bay Bridge. 

Union Square - I'm torn.  I come here myself to shop - but when I do, I set aside half a day and I plan in advance where I'm going because the shopping is scattered over 6 square blocks, so it's really easy to run yourself ragged.  I see a lot of tourist families wandering around, looking tired.  My advice is to consult a map and plot out in advance which specialty shops you want to hit that aren't in your hometown (because most of them are available at your local mall or big city, so why waste your vacation time here?).  

Union Square itself is pretty, and a lot of people stop through here because of the cable cars.  If you just want a bite and to rest your weary feet, try:

• Emporio Rulli at the east end of the Union Square park
• A drink at the Westin St Francis (sadly, you can no longer ride the elevators for a great view without a guest keycard)
• Cheap eats in the Macy's Cellar 
• Indulge just a little eating under the stained glass at the Rotunda at Neiman Marcus.
• 54 Mint is tucked away but worth seeking out for a nice authentic Italian dinner.
• Sears Fine Food has a good breakfast.  Sometimes there's a line, but it usually moves quickly.