Most advocates of saving that I’ve seen in mainstream media are interested foremost in personal finance, not anti-consumerism. To them, the problem isn't that people enjoy spending money. On the contrary, they want to help people spend their money in a way that maximizes the amount of enjoyment derived. Writers like Stanley know that spending a lot of money early in your working life is rarely a way to maximize enjoyment.
What a lot of people don’t realise is that “short-term pleasures” cost a lot more when you’re older. In your 20s and 30s, you don’t need much more than a computer and a bicycle to be perfectly content. You have lots of energy to work, study, take cheap outdoorsy vacations, and cut your own lawn. But at some point, you start to find those things significantly more wearisome. That’s when it’s really nice to have the financial freedom to quit your job, eat in good restaurants, and outsource all of your home maintenance. By far the majority of people won’t achieve that level of financial freedom unless they defer a large proportion of their income from the first half of their career to the second half and to retirement.
Evidently, many people must overcome significant psychological obstacles to save their money. That’s why there are so many personal finance books trying to explain the same idea in different ways. Some emphasize the time value of money. Others, how expenses tend to increase over one’s lifetime. Stanley tries to reduce the urge to spend by showing that many big spenders are not actually rich or financially secure. The success of “The Millionaire Next Door” seems to be evidence that a lot of people find this approach helpful.