The Perils of Aggregates
Via Ann Friedman, Anita Hamilton in Time seeks to debunk guilt-based financial advice for women that, in Ann's words, "tut-tuts women for blowing their retirement savings on a beauty binge at Sephora." The debunking:
Women do spend $1,069--$246 more than men do--on clothing every year, according to the Bureau of Labor Statistics 2004-2005 Consumer Expenditure Survey. But that's chump change compared with what single men spend on car ownership ($846 more than single women), eating out ($752 more), alcoholic drinks ($280 more) and audiovisual gear ($143 more). Cutting back on needless spending isn't a bad idea for anyone, but "renegotiating your credit-card balances or getting a lower cost on your IRA probably saves you a lot more money," says Christian Weller, an economist at the Center for American Progress. "That's much more prudent advice to women than saying 'Don't go buying all those Prada shoes.'"
Fair enough, but I think efforts to analyze this question with those kind of statistics run a bit aground once we put the small matter of class into the picture. One factor holding down single women's expenditures on booze and car ownership is that many, many more single women than single men are primary caregivers for their children. Yet, while single motherhood is a fairly widespread phenomenon in America it's pretty rare among the sort of high-SES women to whom I assume these books are addressed. To really tease out whether or not it's true that the sort of women the advice is addressed to spend more money "frivolously" than do men who are similarly situated would be a difficult statistical task and would, among other things, require a fairly rigorous definition of what sort of women it is we're talking about.
Be all that as it may, the correct thing to look at isn't absolute dollar expenditures, but savings as a proportion of income. That, at least, could tell you whether or not it's actually true that men are more frugal than women. I really think someone should do that study, since whichever way it turns out it can easily be spun into the sort of gender-norm re-enforcing narrative the media craves. For example, women save more than men because they're more cautious, having evolved to keep children safe while men have evolved to embrace risk and kill large animals. Alternatively, women spend more because they're more frivolous, having evolved to maximize resource-investment when young on attracting a mate who is expected to provide for them down the road.