I don't know... our curation rewards are pretty small the begin with (as it is split up in so many different ways!), so losing a similar amount on a post is likely to only cost on the order 0.001/2/3 SP anyway/.. for manual voters, it isn't really such a big deal, and a big whale will likely be wasting much more VP (Mana) to make that happen anyway if they were the only one disagreeing on a controversial but valid post.