Earlier quoted context omitted.
I think you mean craiglist's users' content. Shouldn't the user have the right to do what they want with the classified ad they wrote?
Sure, they have the right to post their content anywhere they want, but after that it's CL's. Same is true with comments, posts on discussion/Q&A sites, etc.
> You automatically grant and assign to CL, and you represent and warrant that you have the right to grant and assign to CL, a perpetual, irrevocable, unlimited, fully paid, fully sub-licensable (through multiple tiers), worldwide license to copy, perform, display, distribute, prepare derivative works from (including, without limitation, incorporating into other works) and otherwise use any content that you post.
Note, it's not exclusive. If you post it to Craigslist they get to use it how they see fit, but you can post it other places.