Well, the first bit, anyway.
I don't think it's a conscious pursuit of intellectual stimulation so much as it is a simple geek impulse to collect and play with data. Joel, if you look at his blog, you'll see other times when he's done this, as with a color naming project, which was actually very fascinating. He just finds it neat. It's okay if that's not what you want in your web comic, but I don't think it's new at all. I could just as easily have seen Randall making a comic like this at the very beginning of xkcd (wasn't the first version based on data, too?), and the store's been around for a while now.

I'm totally buying that map for my boyfriend's office, by the way...