This is true, but I think there's another point that's even more significant: not all network access is the same. In particular, putting some machines in a rack in a colo and connecting to the nearest Internet exchange is really not comparable to Google's networking, which is essentially a worldwide second Internet that is faster and more reliable than the normal Internet, and which carries your packets as far as possible towards their destination before dropping them off at a POP.
(Note: I worked for Google until 3 days ago.)