In addition to what has been said, I think it's a form of risk aversion. Whereas eventually (hopefully!) Sevens and True Religions will be recognized as overplayed and trashy, minimalist jeans are protected from much of the trend cycle. It's easy to see the huge pockets with the horseshoe being out of fashion... but well fitting, quality jeans? Doubtful. If you're spending upwards of $300 on jeans, I think most of us would agree that we'd like for them to last for longer than a season or a few years.