I understand your concerns and I agree, but there is nothing to do about it, as long as people vote for the nodes in question. However it is still very unlikely that something like this may happen, as there are 14 signaturs required to gain control and we are still far away from that number..

I would say the bigger issue is that there are clusters of witnesses at various hosters / cloud providers, which could be an easy attack target e.g. by reporting the nodes. But the same applies to hive itself. It's not too much of an issue there though, as there are simply more witnesses.