Yeah there's some people from a blockchain who think "no downvotes possible" is a better solution to hive, ironically. I just ignore them and some times comment a bit extra so they burn into their upvote mana :p

Although that said I've been thinking about voting up some of my comments I notice that others vote first to counter the downvotes, this way the upvoters still get their curation returns for voting up comments which is something that should be incentivized more in general.