About an hour ego, Reddit updated its user contract. It contains in part:
By submitting User Content to reddit, you grant us a royalty-free, perpetual, irrevocable, non-exclusive, unrestricted, worldwide license to reproduce, prepare derivative works, distribute copies, perform, or publicly display your User Content in any medium and for any purpose, including commercial purposes, and to authorize others to do so.This means that anything you submit to the site is owned by Reddit and they can sue if you make use of it on your own. If you publish it on your website, they can DMCA you and have that content removed.
While this type of contract is present on other sites like Facebook, Reddit presents itself as a different type of internet site which is more user-friendly. It's important to note that this "don't be evil" policy has officially ended as of an hour ago.