I agree that a lot of these mcmansions have no trouble selling. At the end of the day, people HAVE to live somewhere unlike buying a stock so when you are paying 7-8k per month rent to rent a house (guessing on price, but I did find some 5k rentals for < 2k townhomes for rent) for your family of 4 or 5 with a dog, you're stuck having to buy whatever the market prices are.
Bay area housing prices are even more insane than I realized after looking at some of these links posted...