There are a lot of HIVE posts in the trending page which are upvoted by the same group of Whales you mentioned above. I reckon they are following a trail of upvotes and hence when the main curator upvotes, you get all of them voting for you at a particular percentage. It's a great way to reward awesome content creators and boost their confidence to create more of such content. And for curators with heavy HP accounts can compound their investment through curation rewards.
Downside to auto curation is that sometimes it rewards way too extra than the original post deserves. But the PROs are much higher than CONs.
Posted Using LeoFinance Beta