Well, there are lots of reasons. They hope that the research gleaned here will help develop better tools for negotiating a peace between individuals who want to keep their privacy on the Web, and sites that can offer better information as they know their customers better. These results give W3 more fodder to proceed on its course of developing a solution that could be tailored to the privacy preferences of individuals. Clearly, you'll see that the issues are complex and the answers are not simple. I've paraphrased the topline findings.
Internet users value their anonymity.
Most everyone is comfortable providing preference information to Web sites. But when asked about postal address, health, income, or phone numbers, the number of those who felt comfortable sharing that information fell rapidly. In one of the most complicated sections of the study, people were asked whether they would want a browser that could specify their personal privacy preferences to a particular site. Acceptance of the use of cookies and other types of identifiers varies according to their purpose. That said, the notion of a personal identifier has merit based on the specific situation.