I'm in radio and people frequently want to visit radio stations - they have this image of a fun, glamorous, star-studded workplace where anything goes.
They're usually pretty disappointed when they see the sales office, the programming office, a tatty kitchen and a tiny, basic studio in a broom cupboard.
Surely Google is the same - it's acquired a legendary status, but it's just... well, an office, like you go to work in every day. I'm sure there are more interesting places to visit in California.