Realistically, MNC or any other organization knows better than to simply rip content off forums and use it without attribution and agreement from the author. It happens, but rarely. I recall a couple years ago some photos by Ron Shevock (Tyrone Shoelaces) were used without permission by one of the online magazines. It got the author a pretty good reprimand.
The photos and content posted on Epicski are mostly valuable for the content value where it is posted. The commercial "value" in this case equates to views and visits to the site that result in ads being seen. The community value is also important. A thread or article that ends up with big holes blasted out of it when someone wants to take their ball and go home destroys the content that was deleted and seriously damages other content that was posted around it. A broken thread has very little meaning, and is frustrating to those who consider the content will be unchanged when they go back. Arguments, comments or compliments that were directed at a post that no longer exists just looks stupid.
If you ever become aware of improper use of any of your content, you retain all rights to defend that content against unauthorized use by requesting it be retracted, attributed or compensated. On the other hand, there is an implied authorization for the content to be preserved where you posted it on a forum or in an article. By the same token, we have deleted pictures and content that was posted on this site without authorization from the original author, where we have been contacted about that use. There is a whole doctrine of "fair use" and I don't pretend to be much more than peripherally aware of it. Nevertheless, journalist and professionals in the media industry and corporate world know better than to attempt theft of content. It never works out, and there are better and easier ways to achieve the journalistic or commercial goals.
I call BS.
When the TOS states that "You have the ability to edit any of your posts at any time", then there is no implied authorization for preserved content.