Many “news” sites on the Web are really just private link-aggregators with extra ads. They don’t do original reporting; they just link to and summarize an article that someone else wrote, while surrounding it with extra ads.
For example, most news articles that appear on Boing Boing and similar sites are really just links to an article published elsewhere, which was written by an actual reporter for an actual news service. The reporter’s article may be one or two links away from the aggregator’s page, as news services sometimes also link to other news services.
What the link aggregator adds is … ads. Lots of them, usually poor-quality ones. And nobody needs another dose of Outbrain or Taboola.
Example: Boing Boing post — Original article at the BBC.
A reader who’s interested in the subject of the article is going to want to get to the actual source, not just the link-aggregator page. So it’s usually better for the poster here to post the original article, not the link-aggregator page.