Isn't this a problem that can be easily fixed in the same way that HN looks for vote rigging? Seems like one week of work in putting in a fraud detection / collusion / vote weighting system. Also seems to be just a minor growing pain, a feature just ignored so far because it hasn't been important to work on, but once it becomes a bigger concern by the community, I can't think of a good reason why it wouldn't be resolved.
Pandering is hard to stop, but again as the community matures, you'll likely see counter culture develop in the community in the same way HN commenters complain about the first comment to any article being a negative response about the submitted content ;)