Why this strange preference for a digital camera with AA batteries?

Glenn Reynolds has a big post about digital cameras with this line:

Ann Althouse has this small Sony, and a look at her blog will illustrate that it does excellent work. Unlike mine, though, it uses a proprietary rechargeable battery instead of AA batteries. I like the flexibility of being able to pick up fresh batteries anywhere in a pinch, though in truth I seldom have to do that.

But you end up with a clunkier camera! Look how elegantly slim mine is! If you're really worried about running low, buy an extra battery. It's tiny -- 1.4 x .2 x 1.8 inches. Really, that would be much better than having to look around for a store where you could buy batteries, which isn't always so easy anyway.