It's a scenario that plays out thousands of times every day. Traffic jams form in supermarket aisles as shoppers stare at dozens of varieties of salad dressing, yogurt, and pasta sauce, then leave with the same brand they bought last week. Buyers in the market for a new car feel their brains glaze over at the range of makes, models, and options " then decide the old beater is good enough for right now. We can have anything we want, customized down to the smallest detail,...