I knew I was in trouble when I turned into Target's parking lot for the third time that week. At home, I could hardly get much work done for thinking about a pair of sandals I had eyed on an earlier trip. (They were perfect—comfort able but with a little chunky heel that gave me some height.) I left the house with nothing more on my mind than whether they would have a bright red sale sticker on their tag.

The world is too much with us;
late and soon,
Getting and spending,
we lay waste our powers:
Little we see in Nature that is ours;
We have given our hearts away,
a sordid boon!
—William Wordsworth, 1806

Like the Sirens' song, the sandals lured me down the highway and in front of the shoe rack. No luck. They were still full price, $14.99, which under our current family budget may as well have been a hundred.

But instead of heading directly home, I spent an hour there, lifting the colorful, trendy trinkets over my head to peer underneath at the prohibitive price tags. By the time I got back into the car empty-handed, maybe two o'clock in the afternoon, I was exhausted and disappointed. On the way home, pictures of myself—aimless, shuffling through Target—played in my mind like a sad, silent movie.

That day it had been Target, but it could have been any number of retail haunts or thrift shops where my search takes me. At home, I often get overtaken by a feeling that something is missing, so I usually get in the car to go find it. I might be looking for a way to express my innermost self and think picking out a doodad at the Dollar Tree may do that. Or, like a junkie, I roam the streets, trying to escape some kind of inner emptiness by getting an instant fix at Home Depot. Why do I first seek an outlet ...