GOOG is in the S&P 500 and widely held and held by institutions can mean mutual funds and investment companies and I never heard of such rule about high or low PEs.
it's called window dressing. Institutions like to hold the companies that have done the "BEST" so you'll see google 50% return for the year and WE OWN IT... however the catch it that they bought it when it was up 52% and are down 2%... they don't tell you that