No, they stand because that part of the world is used to squatting when they go to the bathroom. The "toilet as throne" model is from the west. Over there, historically, toilets are built into the floor. The toilet bowl is a rounded-rectangle depression in the floor rather than something that sticks out of it. You stand with one foot on either side of the bowl and squat while you do your business.
I prefer Western toilets (I'm American), but think the squat-strategy has a lot of sense to it: you never touch anything, and the squat position angles your body "just right" if you know what I mean. It's just a bit awkward for us (Westerners) when you're not used to holding that body position, though.
There, now I can cross off "get into public internet discussion of pooping strategy" from my life goals list. :)