Millions of folks here in Asia do it, and it's not just for doing #2 mind you. It's an evolved utilitarian default position. Apes do it, birds perched-up on a branch are great at it too.
Sadly though, as cultures and societies change, more "modern" people are less accustomed to doing it, including me! But that's going to change. It's a simple workout of sorts for everything chest down. Try to hold it as long as you can. Don't forget to breath fully afterwards.
Click HERE to see this short and funny film clip on the mechanics of the Asian squat.