I've never been to Google IO, but I'd imagine that you see more Macs for presentations/sessions because they just work on the go. Working at a big tech company in the past, I had a beefy Linux workstation and a Thinkpad that ran Windows that I would only ever use for giving presentations/teaching classes, or while travelling for work.

When my friend used to work there, he was issued a macbook pro which was used mainly to ssh into his Linux workstation from a Chrome tab.

You are only being rude regarding some of the key people working on Android, ChromeOS, Dart, Go and Chrome.

It is a matter of how their lack of cleverness and dedication might affect some of the products you might be using right now.