DjangoCon relies on the generosity of sponsors to keep the conference costs as low as possible, thereby enabling the largest possible attendance. This in turn means that the conference is more useful to those who attend, and that sponsor details are shared with as large an audience as possible.
For a quick overview of sponsorship opportunities download the PDF sponsorship flyer. For full terms and conditions and an application form please take a look at the sponsorship prospectus. To find out what kinds of people attend, take a look at this demographics report. Bottom line: almost everyone responding identified “developer” as their primary or secondary role.