The Government feels that family has a priority to assist in a student's higher education. Outright refusing to help is irrelevant. The US Department of Education deemed refusal to assist in payment, or to fill out financial aid forms are not grounds for dependency status override. A student could be self sufficient for many years, living on their own and paying for their own rent/food/clothing, yet still require parent assistance to better themselves. Some parents want to help, but believe they do not have the means to do so.
If higher education is to better oneself, why is the parent the only one responsible in every single situation?
The Higher Education Act of 1965 will be up for renewal this year. Add in an assistance to all willing, yet unable, potential students out there.