For what it's worth, I've just looked over a few pages of ialdabaoth's comments and they seem consistent with this hypothesis (although the bulk of the comments are now at 0/50%, suggesting that someone subsequently upvoted them back to zero). And ialdabaoth has a ~70% positive rating at the moment, which seems anomalous given the content of their contributions.

As for what to do about it, I'm not sure either. That said, I don't want to see it become a common practice, as it corrupts the information content of karma totals.

So whoever is doing this, please cut it out. You're soiling the commons.