To be honest, the question is not correct. You should've mentioned some factors to be considered.
For Example:
Who earns more ? The webmaster of ABCD.com or the uploader uploading for ABCD.com
If thats the question, then its obvious that the webmaster earns more than the uploader who uploads for ABCD.com
But if that same uploader uploads on EFGH.com too, then chances are there that he earns more than combined income of webmasters of both the sites.
Lets do a case study.
Webmaster A runs a website having 10,000 unique visitors per day. Now, about 60% of the 10k traffic are exposed to uploader B's posts. out of 60%, 45% people will download it and the rest (most probably people with slow connection) will opt out and won't download.
If we count 1 download per visitor, then it'll sum up to 6000 downloads per day and the uploader would earn 150$ from them (if 25$/1000 downloads). But the website gets hit with all 10k users. Most advertising companies pay 0.10-3$/1000 impressions and if we count 20,000 impressions (2X10k - as one homepage, two the post page) then it'll be maximum 60$ (3$X20). But, thats if he has only one 468X60 banner ad. The webmaster will definitely increase this to two banner ads so make it 120$ now. This counts for only impressions (CPM), what about CPC ? the clicks he gets on those banners ? If optimized correctly, then he should get 20% CTR. So that'd be 4000 clicks on the 20k impressions of the banner. This is a significant value and will definitely roll in alot of money.
So the bottom line is, uploader makes less money while the webmaster makes more. If we compare them with our non-virtual lives, then uploaders are like employees and webmasters as the employers. So who earns the most ? employee or the company owner ? That proves it