The point of using an aggregator is that they supply MORE information surrounding your topic that the original source might. The original article or video might be great, but has no surrounding contextually relevant information that might also be useful or helpful. I personally love using sites that aggregate information for me about my hobbies, whether it be games or sports. I find more about what is going on because that site has done the "value added" work of finding and organizing it for me. Saves me time, because there are millions of sites out there that might have great original content, but I will never find them for many reasons. Not the least of which their SEO might stink. So thank you to aggregators whose SEO chops are good!