I also think it is a valid use, but I find it hilarious that those who have been providing blind upvotes in exchange for money are suddenly against blind downvotes.
If they don't like it they should "counter" the votes, that's been their message to the community for 2+ years.
They should take the lumps and brainstorm ways to make their businesses less destructive to the community and content creators.
I have say that I have changed my opinion after having listened to arguments for downvoting bid botted content in Trending. Boosting posts to Trending should always happen at a financial loss. Paying people for putting stuff into Trending is madness because it leads to the prime real estate on Steem being filled with garbage. Trending should have the best organically supported content on Steem to draw eyeballs, which is when advertisers would actually want to pay to put their ads in there.
I think it was @nonameslefttouse put it perfectly:
https://steemit.com/life/@nonameslefttouse/the-state-of-the-nonameslefttouse-address-another-month-down-with-some-time-off-in-between-for-thinking-purposes